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Grammar for exams: clauses, conditionals and sentence structure: Class 12 English
Phrases and clauses, simple, compound and complex sentences, relative and adverbial clauses, the four kinds of conditionals, punctuation and common errors, with practice sentences and answers.
Key points
A phrase is a group of words without a subject and a finite verb, such as in the garden or having finished the work. A clause has a subject and a finite verb. An independent (main) clause makes complete sense alone. A dependent (subordinate) clause does not, and depends on a main clause.
Sentences by structure:
- A simple sentence has one independent clause (The bell rang.).
- A compound sentence has two or more independent clauses joined by and, but, or, so or yet (The bell rang and the students left.).
- A complex sentence has one independent clause and at least one dependent clause (The students left when the bell rang.).
- A compound complex sentence has two or more independent clauses and at least one dependent clause.
Dependent clauses by function:
- Noun clause: acts as a noun (I know that he is honest.).
- Adjective (relative) clause: describes a noun and begins with who, whom, whose, which or that (The book that I bought is useful.).
- Adverb clause: shows time, place, reason, condition, purpose, result or concession (She stayed at home because she was ill.).
A relative clause can be defining, which identifies the noun and takes no commas (The girl who won the prize is my cousin.), or non-defining, which only adds information and is put between commas (My cousin, who lives in Multan, won the prize.). That cannot be used in a non-defining clause.
Conditional sentences have an if clause and a main clause:
- Zero conditional: if + present simple, present simple. It states a general truth (If you heat ice, it melts.).
- First conditional: if + present simple, will + verb. It states a real possibility in the future (If it rains, we will stay at home.).
- Second conditional: if + past simple, would + verb. It states an unreal or unlikely present or future situation (If I were a bird, I would fly.).
- Third conditional: if + past perfect, would have + past participle. It states an unreal past situation (If he had studied, he would have passed.).
In formal English, use were for all persons in the second conditional (If I were you...). Unless means if not, so do not use a negative after it (Unless you work hard, you will fail, not unless you do not work hard).
Subordinating conjunctions join a dependent clause to a main clause: because, although, while, since, unless, until, whereas, so that, if, when, after, before. A comma is placed after a dependent clause that comes first (Although it was raining, we went out.).
Punctuation rules to know:
- Use a full stop at the end of a statement and a question mark after a direct question.
- Use a comma to separate items in a list, after an introductory clause and around non-defining clauses.
- Use a semicolon to join two closely related independent clauses and a colon to introduce a list or an explanation.
- Use an apostrophe for possession (the student's book, the students' books) and for contractions, never for plurals.
Common errors to avoid:
- A run on sentence or comma splice: two main clauses joined with only a comma.
- A sentence fragment: a dependent clause written as a complete sentence.
- A dangling modifier: Walking to school, the rain started. Correct: Walking to school, I felt the rain start.
- Faulty parallelism: She likes swimming, to run and cycling. Correct: swimming, running and cycling.
Study tip: Before you change or combine any sentence, mark the subject and verb of each clause. Decide which is the main idea, and join the rest to it with the right conjunction.
Definitions and flashcards
Say the meaning first, then open the card to check.
Clause
A group of words with a subject and a finite verb.
Independent clause
A clause that can stand alone as a sentence.
Dependent clause
A clause that cannot stand alone and depends on a main clause.
Relative clause
A dependent clause that describes a noun and begins with a relative pronoun.
Conditional sentence
A sentence with an if clause that states a condition and a main clause that states the result.
Subordinating conjunction
A word that joins a dependent clause to a main clause.
Comma splice
The error of joining two independent clauses with only a comma.
Short questions with model answers
These are the kind of questions asked for 2, 3 and 5 marks. Try each one before opening the answer.
Identify the clause: 'The man who lives next door is a doctor.' (2 marks)
Who lives next door is a dependent adjective (relative) clause. It describes the noun the man.
Complete the sentence in the second conditional: If I ___ (have) more time, I ___ (learn) French. (2 marks)
If I had more time, I would learn French.
Correct the sentence: 'If he would have come, I would have told him.' (2 marks)
If he had come, I would have told him. The if clause of a third conditional uses the past perfect, not would have.
Combine into a complex sentence: 'He was tired. He kept working.' (2 marks)
Although he was tired, he kept working.
Punctuate: 'My brother who is a pilot lives in Dubai' as a non-defining clause. (2 marks)
My brother, who is a pilot, lives in Dubai.
Correct the comma splice: 'It was late, we went home.' (2 marks)
It was late, so we went home. (Or: It was late; we went home.)
Common mistakes
- Using will in the if clause of a first conditional (If it will rain...).
- Using a comma before that in a defining relative clause.
- Writing a dependent clause alone as a sentence, which is a fragment.
- Using an apostrophe in a plural noun, such as book's for books.
- Using a negative verb after unless.