Adverb Clauses of Reason: Because, Since, and As

Adverb Clauses of Reason: Because, Since, and As

Adverb clauses of reason explain exactly why something happens by using subordinating conjunctions like because, since, and as. For example, you might say, "I took the bus because my car broke down," or "Since it is raining, we will stay indoors."

In this challenge, you will help detectives, time travelers, and dramatic chefs explain their wild situations while navigating tricky grammar rules. You will practice differentiating reason conjunctions from prepositions like because of or due to (which are followed by noun phrases rather than full clauses). The exercises also cover correct comma punctuation and how to distinguish when since and as indicate a reason rather than a point in time.

You will work through 14 questions in a fun mix of single-choice, multi-choice, drop-down, and drag-and-drop formats.

Try the quiz to check your knowledge!

Adverb

An adverb is a word that modifies a verb, adjective, determiner, clause, preposition, or sentence. Adverbs typically express manner, place, time, frequency, degree, level of certainty, etc., answering questions such as how?, in what way?, when?, where?, and to what extent?. This function is called the adverbial function, and may be realized by single words (adverbs) or by multi-word expressions (adverbial phrases and adverbial clauses).

Adverbs are traditionally regarded as one of the parts of speech. However, modern linguists note that the term "adverb" has come to be used as a kind of "catch-all" category, used to classify words with various different types of syntactic behavior, not necessarily having much in common except that they do not fit into any of the other available categories (noun, adjective, preposition, etc.)

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:

  • 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.
  • 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.

Comma

The comma is a punctuation mark that appears in several variants in different languages. It has the same shape as an apostrophe ( ' ) or single closing quotation mark in many typefaces, but it differs from them in being placed on the baseline of the text. Some typefaces render it as a small line, slightly curved or straight but inclined from the vertical, or with the appearance of a small, filled-in.

The comma is used in many contexts and languages, mainly for separating parts of a sentence such as clauses, and items in lists, particularly when there are three or more items listed. The word comma comes from the Greek, which originally meant a cut-off piece; specifically, in grammar, a short clause.

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.

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."

Phrase

In everyday speech, a phrase may be any group of words, often carrying a special idiomatic meaning; in this sense it is synonymous with expression. In linguistic analysis, a phrase is a group of words (or possibly a single word) that functions as a constituent in the syntax of a sentence, a single unit within a grammatical hierarchy. A phrase typically appears within a clause, but it is possible also for a phrase to be a clause or to contain a clause within it.

Preposition

Prepositions form a closed word class, although there are also certain phrases that serve as prepositions, such as in front of.

A single preposition may have a variety of meanings, often including temporal, spatial and abstract. Many words that are prepositions can also serve as adverbs. Examples of common English prepositions (including phrasal instances) are of, in, on, over, under, to, from, with, in front of, behind, opposite, by, before, after, during, through, in spite of or despite, between, among, etc.

A preposition is usually used with a noun phrase as its complement.

A preposition together with its complement is called a prepositional phrase.

Examples are in England, under the table, after six pleasant weeks, between the land and the sea.

A prepositional phrase can be used as a complement or post-modifier of a noun in a noun phrase, as in the man in the car, the start of the fight; as a complement of a verb or adjective, as in deal with the problem, proud of oneself; or generally as an adverb phrase.

English allows the use of "stranded" prepositions. This can occur in interrogative and relative clauses, where the interrogative or relative pronoun that is the preposition's complement is moved to the start (fronted), leaving the preposition in place. This kind of structure is avoided in some kinds of formal English.

For example:

  • What are you talking about? (Possible alternative version: About what are you talking?)
  • The song that you were listening to ... (more formal: The song to which you were listening ...)

Notice that in the second example the relative pronoun that could be omitted.

Stranded prepositions can also arise in passive voice constructions and other uses of passive past participial phrases, where the complement in a prepositional phrase can become zero in the same way that a verb's direct object would: it was looked at; I will be operated on; get your teeth seen to.

The same can happen in certain uses of infinitive phrases: he is nice to talk to; this is the page to make copies of.

Punctuation

Punctuation in the English language helps the reader to understand a sentence through visual means other than just the letters of the alphabet. English punctuation has always had two complementary aspects: on the one hand, phonological punctuation linked to how the sentence can be read aloud, particularly to pausing; and on the other hand, grammatical punctuation linked to the structure of the sentence. In popular discussion of language, incorrect punctuation is often seen as an indication of lack of education and of a decline of standards.

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 voiceThe report was written yesterday.
  • Modal verbsYou should apply early. / She might be late.
  • Used toI 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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