Examine the following sentences.
- I will say what I like.
- When we went there we found that he had gone.
Sentence 1 consists of two clauses – I will say and what I like. The first is an independent clause which can stand by itself and so it is called the main clause or principal clause. But the second clause cannot stand by itself. It depends on the first clause. It is therefore called a subordinate clause. In sentence 2, we can find three clauses – when we went there, we found, that he had gone. Here the main clause is we found, and the other two are subordinate clauses.
A sentence which consists of one main clause and one or more subordinate clauses is called a complex sentence.
The compound-complex sentence
Look at the following sentences:
- While the man played the violin, the boys sang and the girls danced.
- I knew that he was ill, but I did not know that he was suffering from cancer.
In sentence 1, we can find two main clauses:
a) the boys sang
b) the girls danced
and one subordinate clause:
c) while the man played the violin
In sentence 2, there are two main clauses:
a) I knew
b) but I did not know
and two subordinate clauses
c) that he was ill
d) that he suffered from cancer
A sentence containing two or more main clauses and at least one subordinate clause is called a compound-complex sentence.