The Principal Clause

A clause, as it relates to the sentence, is a defined as a group of words in a sentence which contains both a subject and a predicate.

Every sentence must have at least one principal clause. In sentences with only one clause, the clause and the sentence are the same.

The word “principal” means “head, authority, main, most important, or leader.” The principal clause of a sentence, therefore, is the clause which carries the main idea. A subordinate clause will depend on the principal clause to complete its meaning.

Not all sentences have subordinate clauses, but every sentence must have a principal clause.

In the examples, some of the sentences have both a principal and a subordinate clause. Some of the sentences only have one clause: a principal clause. Sentences with only one principal clause may be called “single clause sentences.”

Look at the sentences below. Can you tell which are single clause sentences and which are multi-clause sentences? Can you identify the principal clause in all the multi-clause sentences?

1. The rain was falling.
2. We were coming home from school when we met an alien.
3. The girls were swimming.
4. The girls were swimming before the rain started to fall.
5. We were driving.
6. We were driving to the hospital after we heard the terrible news.
7. The President was on television.
8. The President was on television when we sat down to have dinner.
9. I was going to work.
10. I was going to work when I heard a loud noise.