Look at these sentences:
‘My children love TO PLAY outdoor games.’
‘Saurav, how many times I have told you TO COMPLETE your home work?’
You will have heard or seen sentences like these many times and must have wondered why the verbs (in theses examples COMPLETE and PLAY) are preceded by TO. PLAY and COMPLETE are base verbs and when TO is added to the base verb, TO PLAY and TO COMPLETE become infinitives. Infinitives are one kind of non-finite verbs, the others being gerunds and participles.
Since TO is a part of the base verb do not treat it as a preposition. The verb is always in its base form and so will not end with '–s', '-ing' or '–ed'. Since the infinitive is a non-finite verb, it cannot be the main verb in a sentence, however, it is possible to use infinitives in many situations. Here are some examples:
Infinitives lend a particular charm to the English language. Take this quiz and learn about infinitives.