Verbs of enabling and obligation

Verbs of enablement and obligation, or causative verbs, often cause problems for students. In English, they have some rather peculiar structures that may not correspond to structures in your own language. Here are the basic rules, to help you master these important verbs.

1. Verbs of obligation and permission:
allow, ask, authorise,  instruct, invite, leave, oblige, permit, require, tell, want, etc.:
After these verbs, the second verb is in the infinitive with to.
   He told me to hurry.
   They allowed us to leave the room.
   The man instructed me to come down.
   I want you to know I love you.
All the verbs listed can be easily used in the passive except want.
   The singer was told to come down.
    He was invited to give a concert.
    She was forbidden to leave the room.
    I was required to fill in a form.
    They were asked to sit down.

2. Verbs of prevention:
Stop, prevent, hinder:
These verbs are followed by “from” and an -ing structure. The word “from” is essential with hinder, optional with stop and prevent.
   He hindered us from starting in time.
   He stopped me (from) falling in the hole.
   They prevented me (from) going out.
“Stop” is not usually used in the passive, but hinder and prevent easily accept passive structures:
   The hooligans were prevented from making trouble.
   We were hindered by the bad weather.
"Forbid" The verb forbid is followed by a full infinitive with to, just like verbs of obligation above.
    I'm going to forbid the children to stay out after 9 o'clock.

3. Causative verbs - verbs of direct authority:
let, make, have.
With these 3 verbs, the second verb form is the infinitive without to.
    I let him do it.
    He made me sit down.
    Have him tell you what he saw!