4.1. However, in some cases the bare infinitive (i.e. the infinitive without the particle to) is used:
- after auxiliary verbs
Do you think she might be joking?
- after modal verbs (except ought, sometimes need and dare)
You could walk round the earth in a year.
- after verbs denoting sense perception such as hear, see, notice, feel, watch.
We both heard him say that he was leaving.
I didn’t see you come in.
- after the verb to let.
She lets her children stay up very late.
Let me just get my coat and I’ll be with you.
- after the verbs to make and to have in the meaning “заставлять, велеть, допускать”.
I made them give me my money back.
Have Mrs. Hansen come in, please.
- after the expressions had better, would rather, would sooner, cannot but, cannot choose but, nothing but, rather than.
You’d better see what she wants.
- after why (not)
Why pay more at other shops? We have the lowest prices.
4.2. Sometimes a bare infinitive or a to-infinitive can be used:
- after the verbs to know, to see, to observe (mostly in perfect tenses)
I’ve never known him (to) pay for a drink.
- after help
Could you help me (to) unload the car?
- after the link verb to be in sentences like:
All I did was (to) give him a little push.
- after and, or, except, but, than, as, like. When two infinitives are joined by and, or, except, etc. the second is often used without to.
I’d like to lie down and go to sleep.
4.3. After the verbs hear, see, make, know, help in the passive the to-infinitive is used.
She was heard to say that she disagreed.
4.4. The particle to is used instead of a whole infinitive if it is easily understood from the context.
“Are you and Gillian getting married? “ “We hope to”.
However, to is often dropped after want and almost always after like, when these are used after conjunctions, for instance when, if, what, as:
Come when you want (to).
4.5. A “split infinitive” is a structure in which to is separated from the rest of the infinitive by an adverb.
I’d like to really understand philosophy.
Split infinitives are quite common in English, especially in an informal style. Some people consider them incorrect or careless, and avoid them by putting an adverb in another position.
He began slowly to get up off the floor.
5.
