Grammar: Verbs of direct authority:

let, make, have. With these 3 verbs, the second verb form is the infinitive without to.
Examples:
I let him do it.
He made me sit down.
Have him tell you what he saw!
Of these three verbs, only one can be used in the passive, make : Example, I was made to take off my skates.
Don’t confuse let and leave: when followed by an object and a subsidiary clause, leave means abandon, quit.
We left him to get on with his work. (i.e. we went away) does not mean the same as We let him get on with his work (i.e. we allowed him to....)