The subject of a sentence is usually a noun or a pronoun. But sometimes, to-infinitives and –ing forms are also used as subjects.
Study the examples given below.
- Swimming is a good exercise.
Here the –ing form ‘swimming’ acts as the subject of the verb ‘is’.
More examples are given below.
- Smoking is injurious to health.
- Singing gives me great pleasure.
- Telling lies can get you into deep trouble.
- Collecting stamps is his hobby.
- Driving very fast on a busy road may lead to an accident.
In each of the following sentences, the subject is an –ing form.
A to-infinitive can also act as the subject of a verb.
Study the example sentences given below.
- To err is human.
- To give advice is easy.
- To follow this advice may be difficult.
- To swim in that sea may be dangerous.
- To drive very fast here is not advisable.
Now study the examples given below. They show another kind of subject a sentence can have.
- What you say is not true.
- Where the police have taken him is not known.
- Why even good people suffer in this world is a great mystery.
As you can see, the subject in each of these sentences is not a word or a phrase, but a group of words which itself looks like a sentence. A group of words of this kind is called a clause. Here the clause functions as a noun and therefore it is called a noun clause.