|1. He promised to write...|
Words such as promises, agreements, orders, offers, requests, advice, and suggestions are often reported with infinitives.
He agreed to pay the bill.
She promised to clean her room.
They agreed to change the color.
|With words ask, advise, tell, and order are used with the structure object +infinitive (but not with promise or offer).|
I told her to wait for me.
She advised me to apply for the position.
The manager ordered Jeff to train the new staff.
|2. He asked her how to...|
It is common to use question word + infinitive structure.
Don't tell her where to study.
I didn't know whether to agree or not.
She asked him how to open the bottle.
|3. Suggest, say: infinitives not used|
After the words suggest or say, infinitive structure isn't commonly used. Instead, that-clause is used with modal verbs.
I told Will that he ought to be patient.
The police said that I musn't drive too fast.
I suggested that they should change the venue.
|It's also possible to use subjunctives and -ing structure after some verbs.|
I suggested trying the exam.
I suggested that he try taking the exam.