Condition Clauses: If, Unless, and Provided That
Condition Clauses: If, Unless, and Provided That
Condition clauses set the rules for when an action can or cannot happen. While if introduces a basic condition, unless means "if not" (e.g., The machine will break unless you clean it), and provided that emphasizes a strict requirement or condition (e.g., You can keep the pet provided that it stays quiet). Choosing the correct word is essential for making sure your sentence's logic makes sense!
In this challenge, you will apply these rules to a variety of entertaining scenarios. You'll help a time traveler avoid erasing history, assist a secret agent with vault alarms, review an eccentric professor's syllabus, and even sign a landlord's unusual pet llama agreement. Along the way, you will practice identifying equivalent statements, such as swapping unless for if not.
You'll work through 12 questions featuring a mix of single-choice, multi-choice, drop-down, and drag-and-drop formats.
Try the quiz to check your knowledge!
Clause
A clause is a grammatical unit built around a verb that typically contains a subject and a predicate. Understanding clauses is essential because they are the core building blocks of every sentence you read, write, or speak.
What makes a clause?
At minimum, a clause needs a verb (the predicate) and, in most cases, a subject — the person or thing the verb says something about. The predicate can also include objects, complements, and modifiers.
- She laughed. — subject (she) + verb (laughed)
- The manager approved the budget yesterday. — subject + verb + object + modifier
Sometimes the subject is left out. This happens regularly in imperative sentences and non-finite clauses:
- Sit down. — no visible subject, but "you" is understood
- Walking home, I noticed the shop was closed. — the -ing clause has no stated subject
Types of clauses
There are two main types:
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Independent clause (also called a main clause) — can stand on its own as a complete sentence. It contains a finite verb.
- I missed the bus.
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Dependent clause (also called a subordinate clause) — cannot stand alone and needs an independent clause to make sense.
- Because I overslept — incomplete on its own
Combine them and you get a complex sentence:
- I missed the bus because I overslept.
A simple sentence has one independent clause. More complex sentences combine independent and dependent clauses in various ways.
Quick check: If you can remove a group of words from a sentence and it still has a subject + finite verb and makes sense on its own, that group is likely an independent clause.
Why clauses matter
Recognizing clause boundaries helps you punctuate correctly, avoid run-on sentences, and build more varied, natural-sounding writing. Once you can spot where one clause ends and another begins, sentence structure becomes much easier to manage.
Ready to practice? Try Complex Sentence for the basics, then move on to Complex Sentence: Adverbials or Participle Clauses: Shortening Sentences with -ing and Having + Past Participle to deepen your skills.
Complex Sentence
A complex sentence has one or more dependent clauses (also called subordinate clauses). Since a dependent clause cannot stand on its own as a sentence, complex sentences must also have at least one independent clause. In short, a sentence with one or more dependent clauses and at least one independent clause is a complex sentence.
A sentence with two or more independent clauses plus one or more dependent clauses is called compound-complex or complex-compound.
In addition to a subject and a verb, dependent clauses contain a subordinating conjunction or similar word. There are a large number of subordinating conjunctions in English. Some of these give the clause an adverbial function, specifying time, place, or manner. Such clauses are called adverbial clauses.
When I stepped out into the bright sunlight, from the darkness of the movie house, I had only two things on my mind.
(S. E. Hinton, The Outsiders))
This complex sentence contains an adverbial clause, When I stepped out into the bright sunlight from the darkness of the movie house.
The adverbial clause describes when the action of the main clause, I had only two things on my mind, took place.
A relative clause is a dependent clause that modifies a noun or noun phrase in the independent clause.
In other words, the relative clause functions similar to an adjective.
- Let him who has been deceived complain. (Miguel de Cervantes, Don Quixote)
- You, who have never known your family, see them standing around you. (J.K. Rowling, Harry Potter and the Sorcerer's Stone)
A noun clause is a dependent clause that functions like a noun.
In the first example, the restrictive relative clause who has been deceived specifies or defines the meaning of him in the independent clause, Let him complain.
In the second example, the non-restrictive relative clause who have never known your family describes you in the independent clause, You see them standing around you.
A noun clause may function as the subject of a clause, or as a predicate nominative or an object.
What she had realised was that love was that moment when your heart was about to burst. (Stieg Larsson, The Girl with the Dragon Tattoo)
In this sentence the independent clause contains two noun clauses.
The noun clause What she had realized serves as the subject of the verb was, and that love was that moment serves as complement.
The sentence also contains a relative clause, when your heart was about to burst.
Conditional Sentence
As is typical for many languages, full conditional sentences in English consist of a condition clause or protasis specifying a condition or hypothesis, and a consequence clause or apodosis specifying what follows from that condition. The condition clause is a dependent clause, most commonly headed by the conjunction if, while the consequence is contained in the main clause of the sentence. Either clause may appear first.
Different types of conditional sentences (depending largely on whether they refer to a past, present or future time frame) require the use of particular verb forms (tenses and moods) to express the condition and the consequence. In English language teaching the most common patterns are referred to as first conditional, second conditional and third conditional; there is also a zero conditional and mixed conditional.
Conjunction
In grammar, a conjunction is a part of speech that connects words, phrases, or clauses that are called the conjuncts of the conjoining construction. The term discourse marker is mostly used for conjunctions joining sentences. This definition may overlap with that of other parts of speech, so what constitutes a "conjunction" must be defined for each language. In English a given word may have several senses, being either a preposition or a conjunction depending on the syntax of the sentence (for example, "after" being a preposition in "he left after the fight" versus it being a conjunction in "he left after they fought"). In general, a conjunction is an invariable grammatical particle and it may or may not stand between the items conjoined.
The definition may also be extended to idiomatic phrases that behave as a unit with the same function, e.g. "as well as", "provided that".
A simple literary example of a conjunction: "the truth of nature, and the power of giving interest". (Samuel Taylor Coleridge's Biographia Literaria)
Conjunctions may be placed at the beginning of sentences: "But some superstition about the practice persists".
Examples
- "But she must give security that she will not marry without royal consent, if she holds her lands of the Crown, or without the consent of whatever other lord she may hold them of."—Magna Carta (1215), translated into modern English
- "But we, or our chief justice if we are not in England, are first to be informed."— Magna Carta (1215), translated into modern English
- "And for the support of this Declaration, with a firm reliance on the protection of divine Providence, we mutually pledge to each other our Lives, our Fortunes and our sacred Honor."
- "But in all such Cases the Votes of both Houses shall be determined by Yeas and Nays, and the Names of the Persons voting for and against the Bill shall be entered on the Journal of each House respectively."—United States Constitution (1787)
- "And the Congress may by general Laws prescribe the Manner in which such Acts, Records and Proceedings shall be proved, and the Effect thereof."—United States Constitution (1787)
- "And this power has been exercised when the last act, required from the person possessing the power, has been performed."—United States Supreme Court Judgment (1803)
- "But, in a larger sense, we can not dedicate, we can not consecrate, we can not hallow this ground." Abraham Lincoln's Gettysburg Address (1863)
- "Yet, if God wills that it continue until all the wealth piled by the bondsman's two hundred and fifty years of unrequited toil shall be sunk, and until every drop of blood drawn with the lash shall be paid by another drawn with the sword, as was said three thousand years ago, so still it must be said "the judgments of the Lord are true and righteous altogether."Abraham Lincoln's Second Inaugural Address (1865)
- "So the inquiries can coexist, though there is much overlap between them."
- "And it appears that it was this latter factor which underlay the dismissal of the appeal by the majority. But it seems to me that the question of whether it is fair, just and reasonable is better considered against the background of whether a sufficiently proximate relationship exists."
- "But the earlier decisions in Pratap Narain Singh Deo and Valsala K. were not brought to the notice of the Court in the two later decisions in Mubasir Ahmed and Mohd. Nasir."
- "And now we have Facebook and Twitter and Wordpress and Tumblr and all those other platforms that take our daily doings and transform them into media."
- "So any modern editor who is not paranoid is a fool".
- "And strikes are protected globally, existing in many of the countries with labour laws outside the Wagner Act model."
Simple Future
The term simple future, future simple or future indefinite, as applied to English, generally refers to the combination of the modal auxiliary verb will with the bare infinitive of the main verb.
Sometimes (particularly in more formal or old-fashioned English) shall is preferred to will when the subject is first person (I or we).
The auxiliary is often contracted to _ 'll_.
This construction can be used to indicate what the speaker views as facts about the future, including confident predictions:
- The sun will rise tomorrow at 6:14.
- It will rain later this week.
It may be used to describe future circumstances that are subject to some condition:
- He will go there if he can.
However English also has other ways of referring to future circumstances. For planned or scheduled actions the present progressive or simple present may be used. There is also a going-to future, common in colloquial English, which is often used to express intentions or predictions (I am going to write a book some day; I think that it is going to rain). Use of the will/shall construction when expressing intention often indicates a spontaneous decision:
- I know! I'll use this book as a door stop.
Compare I'm going to use..., which implies that the intention to do so has existed for some time.
Use of present tense rather than future constructions in condition clauses and certain other dependent clauses is described below under and. The modal verbs will and shall also have other uses besides indicating future time reference. For example:
- I will pass this exam. (often expresses determination in addition to futurity)
- You will obey me! (insistence)
- I will not do it! (negative insistence, refusal)
- At this moment I will tolerate no dissent. (strong volition)
- He hasn't eaten all day; he will be hungry now. (confident speculation about the present)
- One of his faults is that he will make trouble unnecessarily. (habit)
- Shall we get to work? (suggestion)
Future Progressive
The future progressive or future continuous combines progressive aspect with future time reference; it is formed with the auxiliary will (or shall in the first person, the bare infinitive be, and the present participle of the main verb.
It is used mainly to indicate that an event will be in progress at a particular point in the future:
- This time tomorrow I will be taking my driving test.
- I imagine we will already be eating when you arrive.
The usual restrictions apply, on the use both of the future and of the progressive: simple rather than progressive aspect is used with some stative verbs, and present rather than future constructions are used in many dependent clauses. The same construction may occur when will or shall is given one of its other uses, for example:
- He will be sitting in his study at this time. (confident speculation about the present)
Future Perfect
The future perfect combines aspect with future time reference.
It consists of the auxiliary will (or sometimes shall in the first person, as above), the bare infinitive have, and the past participle of the main verb.
It indicates an action that is to be completed sometime prior to a future time of perspective, or an ongoing action continuing up to a future time of perspective (compare uses of the present perfect above).
- I shall have finished my essay by Thursday.
- When I finally search him he will have disposed of the evidence.
- By next year we will have lived in this house for half a century.
For the use of the present tense rather than future constructions in certain dependent clauses.
The same construction may occur when will or shall is given one of its other meanings; for example:
- He will have had his tea by now. (confident speculation about the present)
- You will have completed this task by the time I return, is that understood? (giving instruction)
Future Perfect Progressive
The future perfect progressive or future perfect continuous combines perfect progressive aspect with future time reference.
It is formed by combining the auxiliary will (or sometimes shall, as above), the bare infinitive have, the past participle been, and the present participle of the main verb.
Uses of the future perfect progressive are analogous to those of the present perfect progressive, except that the point of reference is in the future. For example:
- He will be very tired because he will have been working all morning.
- By 6 o'clock we will have been drinking for ten hours.
For the use of present tense in place of future constructions in certain dependent clauses.
The same construction may occur when the auxiliary (usually will) has one of its other meanings, particularly expressing a confident assumption about the present:
- No chance of finding him sober now; he*'ll have been drinking* all day.
Negation
A finite indicative verb (or its clause) is negated by placing the word not after an auxiliary, modal or other "special" verb such as do, can or be. For example, the clause I go is negated with the appearance of the auxiliary do, as I do not go. When the affirmative already uses auxiliary verbs (I am going), no other auxiliary verbs are added to negate the clause (I am not going). (Until the period of early Modern English, negation was effected without additional auxiliary verbs: I go not.)
Most combinations of auxiliary verbs etc. with not have contracted forms: don't, can't, isn't, etc. (Also the uncontracted negated form of can is written as a single word cannot.) On inversion of subject and verb (such as in questions), the subject may be placed after a contracted negated form: Should he not pay? or Shouldn't he pay?
Other elements, such as noun phrases, adjectives, adverbs, infinitive and participial phrases, etc., can be negated by placing the word not before them: not the right answer, not interesting, not to enter, not noticing the train, etc.
When other negating words such as never, nobody, etc. appear in a sentence, the negating not is omitted (unlike its equivalents in many languages): I saw nothing or I didn't see anything, but not (except in non-standard speech) I didn't see nothing. Such negating words generally have corresponding negative polarity items (ever for never, anybody for nobody, etc.) which can appear in a negative context, but are not negative themselves (and can thus be used after a negation without giving rise to double negatives).
B1 | Intermediate
B1 is the intermediate level of the Common European Framework of Reference for Languages (CEFR). It marks the point where you move beyond survival English and start expressing yourself with real independence — describing experiences, explaining opinions, and handling everyday situations without a script.
What a B1 user can do
At this level, you're expected to:
- Understand the main points of clear, standard speech and writing on familiar topics — work, school, travel, hobbies.
- Handle most travel situations in English-speaking environments.
- Produce simple connected text on topics you know or care about.
- Describe experiences, events, hopes, and plans, and give brief reasons and explanations for your opinions.
- Communicate in routine tasks that require a straightforward exchange of information.
What B1 grammar looks like
B1 is where grammar starts to get more layered. You're not just forming basic sentences anymore — you're combining ideas, using different tenses with more precision, and starting to handle structures like the passive voice, modal verbs for necessity and possibility, and gerunds vs. infinitives. You're also expected to build complex sentences with linking words and dependent clauses.
Typical B1 grammar areas include:
- Future tenses — distinguishing will, going to, and the present continuous for future plans
- Passive voice — The report was written yesterday.
- Modal verbs — You should apply early. / She might be late.
- Used to — I used to live in Berlin.
- Verb patterns — knowing whether a verb takes a gerund, an infinitive, or both (I enjoy reading vs. I decided to leave)
What B1 doesn't mean
B1 speakers still hesitate, make grammatical errors, and sometimes struggle with less familiar topics. That's normal. The key difference from A2 is that you can keep a conversation going and get your point across even when things aren't perfect. The step up to B2 involves handling more abstract topics, understanding nuance, and producing more complex, accurate language.
Self-check: Can you tell a friend about a recent trip — what happened, what you liked, and what you'd do differently — without switching to your native language? If yes, you're likely operating at B1 or above.
Ready to find out where you stand? Try Are you B1/Intermediate? Test your English CEFR Level to figure out!, then build your skills with challenges like Basics. Passive Voice, Basics. Modal verbs, and Used to.
B2 | Upper Intermediate
B2, or Upper Intermediate, is the fourth level on the CEFR scale. It marks the point where you move from "getting by" to genuinely comfortable communication — handling complex topics, expressing nuanced opinions, and understanding most of what you read or hear in real-world contexts.
What a B2 user can do
At this level, you're expected to:
- Understand complex texts on both concrete and abstract topics, including technical discussions in your own field.
- Follow extended speech and lectures, even when the structure isn't entirely clear, as long as the topic is reasonably familiar.
- Interact fluently and spontaneously enough that conversations with native speakers flow naturally — without strain on either side.
- Produce clear, detailed text on a wide range of subjects, using connectors and cohesive devices to build well-structured arguments.
- Explain and defend a viewpoint on a topical issue, weighing the advantages and disadvantages of different options.
- Recognize implicit meaning — reading between the lines in demanding, longer texts.
What B2 grammar looks like in practice
B2 is where grammar stops being about isolated rules and starts being about flexibility and precision. You're expected to control structures like:
- Advanced conditionals and mixed conditionals — moving beyond simple if-clauses to express hypothetical and counterfactual meaning.
- Passive voice in varied tenses and contexts, not just present and past simple.
- Reported speech with correct sequence of tenses, including backshifting and reporting verbs.
- Participle clauses and the distinction between participles and gerunds.
- Comparative and superlative structures beyond basic -er/-est, including double comparatives and qualifying expressions.
Errors still happen at B2, but they rarely cause misunderstanding. The goal is controlled, flexible use of language across social, academic, and professional settings.
How B2 fits in the CEFR progression
B2 builds directly on the foundations of B1 (Intermediate) and prepares you for C1 (Advanced). Many university entrance exams, professional certifications, and immigration requirements target B2 as the minimum standard.
Self-check: If you can read a newspaper editorial, follow most of a TED talk without subtitles, and write a clear essay arguing a position — you're likely operating at B2.
Ready to test yourself? Try Is your English level B2/Upper Intermediate? or practise specific B2 grammar with challenges like Basics. Advanced Conditionals And "wish", Basics. Passive Voice, and Sequence of Tenses in Indirect Speech.
Difficulty: Medium
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