A clause is a group of words consisting of a subject and a verb.

There are two types of clauses: coordinate clauses and subordinate clauses

Consider the sentence given below:

• They set out on their journey when the sun rose.

The above sentence has two clauses:

1. They set out on their journey
2. …when the sun rose

Here the first clause makes complete sense and can stand independently. However, the second clause does not make much sense without the first clause. Its existence depends on the first clause and hence it is a subordinate clause.

The subordinate clause can go before or after the main clause.

Study the examples given below.

• Though he worked hard he could not pass the test. (Here the subordinate clause ‘though he worked hard’ goes before the main clause.)
• He could not pass the test though he worked hard. (Here the subordinate clause goes after the main clause.)

Subordinate clauses are introduced by subordinating conjunctions. Examples are given below: when, after, before, since, for, till, until, because, since, as, though, although, if, whether etc.

A subordinate clause cannot make a sentence because it cannot stand alone. It has to be attached to a main clause. A sentence that consists of one main clause and one or more subordinate clauses is called a complex sentence.