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Grammar Reference

Modal Verbs (Complete Guide)

Master every modal verb and conjunction — meaning, structure, rich examples, common mistakes, and special topics. All in one place.

Core Modal Verbs

These are the primary modal auxiliary verbs in English. They never change form, always come before the base verb, and never take -s, -ing, or -ed.

Semi-Modals & Alternatives

These expressions function like modals but use full verb forms. They can be conjugated and used in all tenses.

have to

Have to / Don't have to

External obligation (rules, laws, circumstances) vs. absence of obligation.

Structure
Present
Subject + have to / has to + base verb
Past
Subject + had to + base verb
Negative
Subject + don't/doesn't have to + base verb (NOT an obligation)
I have to submit the report by noon. (external rule)
She has to wear a uniform at work.
You don't have to come if you're busy. (no obligation — choice)
He didn't have to pay — it was free.
Must vs have to: "must" = personal conviction; "have to" = external rule. Both express obligation.
"Don't have to" ≠ "mustn't": "You don't have to sign" = optional. "You mustn't sign" = forbidden.
  • "He have to go" ❌ → 3rd person: he has to go.
  • "Don't have to" does NOT mean "must not" — it means there's no obligation.
  • Future: use will have to — "You will have to wait."
need to

Need to / Don't need to

Necessity and absence of necessity. Softer than must.

Structure
Regular verb
Subject + need to + base verb (conjugates: needs to)
Negative
Subject + don't / doesn't need to + base verb
Modal use (rare/formal)
Need + Subject + base verb ? / Subject + need not + base verb
You need to rest after surgery.
She doesn't need to bring anything.
Needn't (modal form): "You needn't worry" — formal/British.
"Need I say more?" — rhetorical question, formal.
"You needn't have cooked so much" = you did it, but it wasn't necessary.
be able to

Be able to

Alternative to can/could — usable in all tenses where modals cannot go.

Structure
All tenses
Subject + am/is/are/was/were/will be + able to + base verb
She is able to work under pressure.
He was able to escape. (specific past success — "could" ❌ here)
They will be able to travel next year. (future — "can" ❌ for future ability)
I haven't been able to sleep lately.
Use be able to after another modal: "You might be able to help."
After to: "I'd love to be able to speak Japanese."
ought to

Ought to

Similar to should — moral obligation or expectation. More formal, less common.

Structure
Affirmative
Subject + ought to + base verb (always with "to" unlike core modals)
Negative
Subject + ought not to (oughtn't to) + base verb
You ought to call your parents more often.
He oughtn't to have done that.
Ought to ≈ should, but sounds more objective/moral.
Unlike core modals, ought to is followed by to + base verb.
"Ought he to attend?" — very formal; in conversation, prefer "Should he attend?"
used to

Used to

Past habits or states that no longer exist. Only used in the past.

Structure
Affirmative
Subject + used to + base verb
Negative
Subject + didn't use to / usedn't to + base verb
Question
Did + Subject + use to + base verb ?
I used to play the piano every day.
She used to live near here.
He didn't use to like vegetables.
Used to vs would: both for past habits, but used to can describe past states too — "I used to be shy" (not "I would be shy").
⚠ Be used to (= accustomed to) is different: "I am used to waking up early."
⚠ Get used to (= become accustomed): "She's getting used to the cold weather."
"I am used to swim" ❌ → "I am used to swimming" — "be used to" takes -ing.
  • used to + base verb — past habit/state (no longer true): "I used to smoke."
  • be used to + -ing / noun — accustomed to: "I am used to the noise."
  • get used to + -ing / noun — becoming accustomed: "He's getting used to driving on the left."

Special Topics

Deep-dive into the most important advanced modal uses: certainty, politeness, obligation differences, past modals, and common grammar traps.

  • must — 95–100% certain (positive): "She must be home — the light is on."
  • can't / couldn't — 95–100% certain (negative): "That can't be right — it's impossible."
  • should — fairly certain / expected: "The package should arrive today."
  • may — ~50% possibility: "He may come, I'm not sure."
  • might / could — ~30–40% possibility: "It might snow tomorrow."
  • Scale: must → should → may → might/could → can't
  • "She must be tired" (present deduction) vs "She must have been tired" (past deduction).
  • Never use must not for deduction — use can't: "She can't be 50, she looks 30!"
The lights are off — everyone must have left. (past deduction)
That can't be Ahmed — he's in Dubai! (present impossibility)
She might be stuck in traffic. (present possibility, ~30%)
He could be the one who called. (possible, not certain)
  • Can you...? — informal/casual: "Can you help me?"
  • Could you...? — more polite, slightly formal: "Could you close the door?"
  • Would you...? — formal request: "Would you like to sit down?"
  • Will you...? — less formal than would: "Will you pass the salt?"
  • May I...? — formal asking for permission: "May I ask a question?"
  • Shall I...? — offer to do something: "Shall I carry that for you?"
  • Would you mind + -ing — very polite: "Would you mind moving your car?"
Politeness scale (most → least formal): May I → Could you → Would you → Will you → Can you
"Would you mind if I opened the window?" — note past tense after "mind if."
"Can I help?" — informal offer. "Shall I help?" — more formal.
  • Must — strong personal obligation or inner conviction: "I must call her — she needs me."
  • Have to — external obligation (rules, laws, circumstances): "I have to wear a uniform at work."
  • Should — advice, recommendation, mild obligation: "You should drink more water."
  • Ought to — moral obligation, similar to should but more formal: "You ought to apologise."
  • Need to — necessity, slightly softer than must: "She needs to see a doctor."
Must = "I feel strongly this is necessary." Have to = "The rules/situation require it."
Mustn't = FORBIDDEN. Don't have to = NOT REQUIRED (you have a choice).
Strength: must ≥ have to > need to > should / ought to
Structure
Modal + have + past participle
  • Should have done — regret or criticism: "I should have studied more." / "You shouldn't have said that."
  • Could have done — missed possibility: "She could have won, but she gave up."
  • Might have done — past possibility: "He might have left already."
  • Must have done — past deduction (certain): "You must have been exhausted."
  • Can't have done — past impossibility: "She can't have forgotten — she just texted me."
  • Would have done — 3rd conditional (unreal past): "I would have come if you had asked."
  • Needn't have done — did it but it was unnecessary: "You needn't have cooked so much."
He must have been exhausted after that journey. (past certainty)
She could have called — why didn't she? (missed opportunity)
They might have taken the wrong exit. (past possibility)
You should have told me earlier! (regret/criticism)
It can't have been easy for her. (past impossibility/deduction)
  • Modal + to ❌: Core modals (can, will, must, should, may, might, shall, would, could) are NEVER followed by to. "I can to swim" ❌ → "I can swim."
  • Modal + -ing ❌: Modals are followed by the base verb, not -ing. "She should going" ❌ → "She should go."
  • Double modals ❌: Never stack two core modals: "I will can do it" ❌ → Use be able to: "I will be able to do it."
  • Third-person -s ❌: Modals never add -s: "She cans" ❌, "He wills" ❌, "She musts" ❌.
  • Pronunciation: "could" /kʊd/, "would" /wʊd/, "should" /ʃʊd/ — the "l" is silent in all three.
  • Modal + have past form: "should have gone" — spoken quickly as "should've gone" — NOT "should of gone" (common spelling error).
  • Mustn't vs. don't have to: the most dangerous confusion — always check which meaning you intend (prohibition vs. no obligation).
  • May not vs can't: "It may not be true" = possibly not true. "It can't be true" = impossible.
  • can / could — ability context: manage, skill, talent, succeed, achieve
  • may / might — uncertainty context: perhaps, possibly, probably, not sure, I think, maybe
  • must — obligation context: required, rule, law, necessary, essential, compulsory
  • should — advice context: recommend, suggest, advise, it's better if, ought
  • will / would — future/conditional context: tomorrow, if…then, planning, promise, offer
  • shall — offer context: let me, may I help, should I, we together
perhapsprobably definitelyimpossible requiredallowed advicerecommend if…thenI'm sure I'm not sureability forbiddenoptional

Conjunctions — Complete Guide

Conjunctions are the glue of English. They connect words, phrases, and clauses. There are three main types: Coordinating, Subordinating, and Correlative — plus Conjunctive Adverbs.

Coordinating (FANBOYS) Subordinating Correlative (Pairs) Conjunctive Adverbs
A Coordinating Conjunctions — FANBOYS
F·A·N·B·O·Y·S

What Are Coordinating Conjunctions?

They join two equal, independent elements — words, phrases, or complete clauses. The acronym FANBOYS is the standard mnemonic: For, And, Nor, But, Or, Yet, So.

Structures
Joining two independent clauses
Independent clause + [conjunction] + independent clause
Joining two words / phrases
Word/phrase + [conjunction] + word/phrase (no comma needed)
Punctuation rule: When a coordinating conjunction joins two independent clauses, place a comma before the conjunction. When joining only words or phrases, no comma is needed.
forandnor butoryetso
for

For — Reason / Cause

Introduces a reason or explanation. Formal; rarely used in speech. Similar to "because" but always follows the main clause.

Cause: She stayed home, for she was feeling ill. (= because)
He didn't answer, for he hadn't heard the question.
We must act now, for time is running out.
★ Notes & Tricky Cases
"For" as a conjunction is formal/literary — in everyday speech, use because instead.
"For" as a conjunction always comes between two clauses, never at the start of a sentence.
"For" as a preposition (time/purpose) is different: "I've lived here for five years."
and

And — Addition

Adds one idea to another. Can join words, phrases, or clauses.

She bought bread and butter. (joining nouns)
I finished my homework, and then I watched TV. (joining clauses)
He is tall and athletic. (joining adjectives)
They laughed and cried at the same time.
★ Notes & Tricky Cases
And can express consequence: "Study hard and you'll pass" (= if you study hard).
In lists of 3+: "red, white, and blue" — the Oxford comma before and is optional but often recommended.
Starting a sentence with And is acceptable in modern English for emphasis, though traditionally avoided in formal writing.
"And so on", "and so forth", "and the like" — common fixed expressions.
nor

Nor — Negative Addition

Adds another negative idea after a negative statement. Often paired with neither.

She didn't call, nor did she send a message. (inverted subject after nor)
He can't swim, nor can he cycle.
Neither the manager nor the staff knew about it.
★ Notes & Tricky Cases
After nor joining two clauses, the subject and auxiliary invert: "nor did she" — NOT "nor she did."
Neither … nor is the standard correlative pair (covered in Section C below).
"Not … nor" ❌ — use "not … or" or "neither … nor": "I don't like tea or coffee."
but

But — Contrast / Exception

Introduces contrast, contradiction, or an exception. One of the most common conjunctions in English.

He studied hard, but he still failed. (contrast)
She is smart but lazy.
I wanted to go, but I was too tired.
Everyone was invited but him. (= except — preposition use)
★ Notes & Tricky Cases
But can also mean except as a preposition: "Nobody but me knew."
But vs however: "but" is a conjunction (connects clauses directly); "however" is a conjunctive adverb (needs a semicolon or new sentence).
"But yet" is redundant — use one or the other.
Not only … but also — correlative pair: "Not only did she sing, but she also danced."
or · yet · so

Or, Yet & So

Or = choice/alternative. Yet = contrast (stronger than but). So = result/consequence.

Hurry up, or you'll miss the bus. (alternative / warning)
Would you like tea or coffee? (choice between two)
It was cold, yet they went swimming. (surprising contrast)
She tried hard, yet she couldn't solve it.
I was hungry, so I made a sandwich. (result)
The door was open, so I walked in.
★ Notes & Tricky Cases
Or with imperatives = warning: "Be quiet, or I'll ask you to leave."
Either … or is the correlative form: "Either you come now, or you stay home."
Yet is stronger and more formal than but — it implies surprise or unexpectedness.
So as a conjunction ≠ so as an adverb of degree: "She is so tall" (adverb) vs. "It rained, so we stayed in" (conjunction).
"So that" is a subordinating conjunction of purpose — different from coordinating so: "I left early so that I wouldn't be late."
  • Comma splice — joining two independent clauses with only a comma and no conjunction: "She came home, she was tired" ❌ → "She came home, and she was tired."
  • Missing comma before a conjunction joining two full clauses: "She studied hard but she failed" ❌ → "She studied hard, but she failed."
  • Using so and because together: "Because it rained, so we stayed in" ❌ — use one or the other.
  • Confusing yet (conjunction) with yet (adverb): "I haven't eaten yet" (adverb) vs. "It was cold, yet we swam" (conjunction).
  • Using nor without inverting the subject: "nor she came" ❌ → "nor did she come."
  • For → reason/cause (formal): because, since, as
  • And → addition, sequence: also, too, in addition, furthermore
  • Nor → negative addition: neither, not either
  • But → contrast, exception: however, on the other hand, except
  • Or → choice, alternative, warning: otherwise, either, alternatively
  • Yet → strong contrast/surprise: nevertheless, still, however
  • So → result, consequence: therefore, thus, as a result
B Subordinating Conjunctions
subordinating

What Are Subordinating Conjunctions?

They introduce a dependent (subordinate) clause that cannot stand alone. The dependent clause adds context — time, cause, condition, concession, purpose, etc. — to the main clause.

Structures
Conjunction mid-sentence
Main clause + [subord. conj.] + dependent clause (no comma)
Conjunction at start
[Subord. conj.] + dependent clause , main clause (comma after dependent clause)
Key rule: When the dependent clause comes first, use a comma. When it comes after the main clause, usually no comma.
Time

Time Conjunctions

Show when something happens in relation to something else.

whenwhileas afterbeforeuntil / till sinceonceas soon aswhenever
When she arrived, everyone cheered. (simultaneous/subsequent)
I was reading while he was cooking. (parallel actions)
Call me as soon as you land. (immediately after)
Don't leave until I get back. (up to a point)
Since she moved away, I've felt lonely. (from a point in the past)
I'll call you before I leave. (prior to)
★ Tricky Cases
When vs while: "when" = a point in time; "while" = a duration: "The phone rang when I was eating" vs. "I listened to music while I drove."
After time conjunctions, use present simple for future meaning: "I'll call you when I arrive" — NOT "when I will arrive."
Since can mean time OR cause: "Since you're here, help me" (cause) vs. "Since he left" (time).
Once = as soon as / after: "Once the meeting ends, we can leave."
Cause

Cause & Reason Conjunctions

Explain why something happens.

becausesinceas now thatseeing thatinasmuch as
She stayed home because she was sick. (direct cause — most common)
Since you asked, I'll tell you the truth. (given that)
As it was raining, we cancelled the picnic. (formal/literary cause)
Now that you've graduated, what's next?
★ Tricky Cases
Because vs because of: "because" introduces a clause; "because of" introduces a noun phrase: "because it rained" vs. "because of the rain."
Avoid starting a sentence with because in formal writing unless the main clause follows: ❌ "Because she left." (fragment)
As (cause) is weaker and more formal than because; since implies the listener already knows the reason.
Condition

Conditional Conjunctions

Express conditions under which something will happen (or not).

ifunlessprovided that as long ason condition thatsupposingin case
If you study, you will pass. (1st conditional — real)
Unless you leave now, you'll be late. (= if not)
You can come as long as you behave.
Take an umbrella in case it rains. (precaution)
Provided that you meet the deadline, the deal is yours.
★ Tricky Cases
Unless = if not: "Unless you hurry" = "If you don't hurry." Do NOT use "unless … not" together.
In case ≠ if: "in case" = as a precaution (we do it now to prepare); "if" = only if the condition is met.
After conditional conjunctions, future is expressed with present tense: "If she comes" — NOT "if she will come."
Supposing / suppose = informal "what if": "Supposing they reject it?"
Concession

Concession Conjunctions

Introduce a contrasting idea that doesn't prevent the main clause from being true.

althoughthougheven though even ifwhilewhereasdespite the fact that
Although it was raining, we went out. (concession)
She passed the exam even though she hadn't studied.
Whereas he is outgoing, she is shy. (contrast between two facts)
While I agree with you, I still have concerns. (concession — formal)
★ Tricky Cases
Although / though / even though: all similar. Even though is strongest (real fact). Even if = hypothetical.
Although vs despite: "although" + clause; "despite" + noun/gerund: "Although she tried" vs. "Despite trying."
"Although … but" ❌ — never use both: "Although he was tired, but he continued." → drop "but."
Whereas highlights a direct contrast (often factual): "Cats are independent, whereas dogs are loyal."
Purpose · Result · Comparison

Purpose, Result & Comparison Conjunctions

Express why, with what outcome, and in what way comparisons are made.

so thatin order thatso … that such … thatas … asthanas ifas though
She spoke slowly so that everyone could understand. (purpose)
It was so hot that we couldn't sleep. (result/degree)
He runs as fast as a professional athlete. (comparison equal)
She is taller than her brother. (comparison unequal)
He spoke as if he knew everything. (unreal comparison)
★ Tricky Cases
So that (purpose) vs so (result): "I left early so that I wouldn't be late" (purpose) vs. "I was tired, so I left" (result).
As if / as though + past tense = unreal: "She talks as if she were the boss."
"Than me" vs "than I": both are accepted; formal English prefers "than I am."
So … that vs such … that: "so" precedes an adjective/adverb; "such" precedes a noun phrase: "so tired that" vs. "such a hot day that."
  • Using will after time/conditional conjunctions: "When she will arrive" ❌ → "When she arrives."
  • Although … but — double concession: "Although it was late but I stayed" ❌ → drop but.
  • Because … so — double result: "Because it rained so we stayed" ❌ → use one: "Because it rained, we stayed" or "It rained, so we stayed."
  • Using unless … not: "Unless you don't call" ❌ — unless already contains negation: "Unless you call."
  • Fragment sentences: starting a sentence with a subordinating conjunction but not completing the main clause: "Because he left." ❌
  • Confusing while (time/concession) with whereas (direct contrast): they overlap but "whereas" is purely contrastive.
  • Time: when, while, as, after, before, until, till, since, once, as soon as, whenever, by the time
  • Cause/Reason: because, since, as, now that, seeing that, inasmuch as
  • Condition: if, unless, provided that, providing, as long as, in case, supposing, on condition that
  • Concession: although, though, even though, even if, while, whereas, despite the fact that
  • Purpose: so that, in order that, lest (formal/archaic)
  • Result/Degree: so … that, such … that
  • Comparison: as … as, than, as if, as though, just as
  • Place: where, wherever, everywhere
  • Manner: as, as if, as though, how
C Correlative Conjunctions — Pairs
correlative

What Are Correlative Conjunctions?

They always appear in pairs and work together to join grammatically equal elements. The two elements must be parallel in structure.

both … and either … or neither … nor not only … but also whether … or such … that so … that as … as no sooner … than hardly … when
Parallelism rule: Both parts of a correlative conjunction must be followed by the same grammatical structure (both noun + noun, verb + verb, adjective + adjective, etc.).
both … and

Both … And

Emphasises that two things are equally true or applicable.

Both she and her brother speak Arabic. (equal emphasis on two subjects)
He is both talented and hardworking.
I enjoy both reading and writing.
★ Notes
Both … and always takes a plural verb: "Both the teacher and the student were present."
Parallel structure required: ❌ "Both running and to swim" → ✓ "Both running and swimming."
either … or

Either … Or

Presents two alternatives. Only one of the options is chosen or applies.

Either you come now, or you miss the bus.
You can have either tea or coffee.
Either the manager or his assistant will contact you.
★ Notes
Verb agreement with either … or: the verb agrees with the subject closest to it: "Either the students or the teacher is responsible."
Parallelism: "Either study or go to bed" ✓ (both verbs). ❌ "Either study or going."
neither … nor

Neither … Nor

Negates both options equally. The sentence already carries negation — no extra not is needed.

Neither the food nor the service was good.
She neither called nor sent a message.
Neither of them knew the answer.
★ Notes
Same verb agreement rule as either … or: verb agrees with the nearest subject.
"Neither … nor … not" ❌ — double negation: "Neither did he call nor did he not write." → remove "not."
When used alone: "Neither is correct" = neither of the two mentioned things.
not only … but also

Not Only … But Also

Adds emphasis by listing two things, with the second being more surprising or important.

Not only did she win the prize, but she also broke the record.
He is not only a doctor but also a writer.
Not only is she talented, but she is also dedicated.
★ Notes
When not only starts a sentence, the subject and auxiliary invert: "Not only did she come, but she also helped."
"Also" can be omitted in informal speech: "Not only was it late, but it was also cold" → "but it was cold."
Parallelism is critical: "not only singing but also dancing" ✓
no sooner … than · hardly … when

No Sooner … Than & Hardly … When

Express that one thing happened immediately after another. Both require subject–auxiliary inversion.

No sooner had I sat down than the phone rang.
Hardly had she left when it started to rain.
Scarcely had he opened the door when he heard a noise.
★ Notes
Always use Past Perfect + inversion in the first clause: "No sooner had I left …"
These are formal/literary constructions, common in written English and advanced exams.
"No sooner … when" ❌ → must use than. "Hardly … than" ❌ → must use when.
  • Faulty parallelism — the most common error: "Either to eat or sleeping" ❌ → "Either to eat or to sleep / either eating or sleeping."
  • Neither … or ❌ → must be neither … nor.
  • Both … as well as ❌ (redundant) → use both … and or … as well as … alone.
  • No sooner … when ❌ → no sooner … than. Hardly … than ❌ → hardly … when.
  • Subject–verb agreement: with either … or and neither … nor, verb agrees with the closer subject: "Neither the students nor the teacher was ready."
  • Not only at the start without inversion: "Not only she came late" ❌ → "Not only did she come late."
D Conjunctive Adverbs
adverbs

Conjunctive Adverbs

These are adverbs that act as connectors between two independent clauses. Unlike true conjunctions, they require a semicolon (or a full stop) before them, and a comma after them.

Structure
Standard (semicolon)
Independent clause ; [conjunctive adverb] , independent clause
Two sentences
Independent clause. [Conjunctive adverb] , independent clause.
Mid-sentence (moveable)
Independent clause ; subject , [conjunctive adverb] , predicate
Critical difference from conjunctions: You cannot join two independent clauses with a conjunctive adverb and only a comma — that creates a comma splice. Always use a semicolon or a new sentence.
howevertherefore moreoverfurthermore neverthelessnonetheless consequentlythus otherwisemeanwhile insteadindeed besideslikewise stillthen in factas a result on the other hand
Contrast

Contrast — however, nevertheless, nonetheless, still, on the other hand

She trained for months; however, she didn't win. (contrast)
The plan had flaws; nevertheless, they proceeded.
It was expensive. Nonetheless, we bought it.
She failed; she, however, refused to give up. (mid-sentence — moveable)
He was unqualified. On the other hand, he had great potential.
Cause/Result

Cause & Result — therefore, consequently, thus, as a result

She didn't study; therefore, she failed.
The road was icy; consequently, many accidents occurred.
He worked hard. As a result, he was promoted.
The files were corrupted; thus, we lost the data.
Addition

Addition — moreover, furthermore, besides, in addition, likewise

The price is right; moreover, the quality is excellent.
She speaks Arabic; furthermore, she has a degree in linguistics.
I don't want to go. Besides, I have too much work.
He arrived on time; likewise, his colleagues were punctual.
Other

Other Key Conjunctive Adverbs — otherwise, meanwhile, instead, indeed

Hurry up; otherwise, we'll miss the train. (condition/warning)
She was preparing dinner; meanwhile, the children were doing homework. (simultaneous)
Don't shout; instead, speak calmly. (alternative action)
He said he would help. Indeed, he arrived first. (confirmation/emphasis)
  • Comma splice — using only a comma: "She was tired, however she continued" ❌ → "She was tired; however, she continued."
  • Treating conjunctive adverbs like conjunctions (no semicolon): "I was tired, therefore I left" ❌ → "I was tired; therefore, I left."
  • Forgetting the comma after the conjunctive adverb: "However she continued" ❌ → "However, she continued."
  • Confusing however (conjunctive adverb) with but (conjunction): "but" directly joins clauses with a comma; "however" needs a semicolon.
  • Therefore vs so: "so" is a conjunction (comma + so); "therefore" is a conjunctive adverb (semicolon + therefore + comma).
  • Coordinating (FANBOYS): Use a comma + conjunction to join two independent clauses. No comma needed for phrases.
  • Subordinating: Dependent clause first → comma after it. Dependent clause last → usually no comma. Never use will after time/conditional conjunctions.
  • Correlative: Both parts must join parallel structures. Verb agrees with the closest subject (for either…or / neither…nor).
  • Conjunctive adverbs: Always use a semicolon (or period) before them, and a comma after. They are moveable within the second clause.
  • Quick test — if you can remove the connecting word and still have two complete sentences, you likely need a semicolon (conjunctive adverb) rather than a comma (conjunction).
  • Addition: and, both…and, not only…but also, moreover, furthermore, besides, in addition, likewise, also
  • Contrast: but, yet, although, though, even though, whereas, while, however, nevertheless, nonetheless, on the other hand, still
  • Cause/Reason: because, since, as, for, now that, inasmuch as
  • Result/Consequence: so, so that, therefore, consequently, thus, as a result, hence
  • Condition: if, unless, provided that, as long as, in case, on condition that, supposing
  • Time: when, while, as, after, before, until, since, once, as soon as, whenever, by the time, no sooner…than
  • Concession: although, though, even though, even if, despite the fact that, granted that
  • Purpose: so that, in order that, lest
  • Alternative: or, either…or, otherwise, instead
  • Emphasis/Clarification: indeed, in fact, that is, namely