Certain words and expressions are followed by particular prepositions. Here is a list of the most common combinations.
She insisted on paying for the drinks.
He was always interested in politics.
People have always been kind to me.
She is lacking in tact.
The little girl laughed at the poor beggar.
We will all laugh about this one day.
Why don’t you listen to me?
What are you looking at?
Look for (= try to find)
I am looking for my keys.
Her marriage to James didn’t last very long.
She is nice to everybody.
Operate on (a patient)
They operated on her yesterday evening.
Pay for (something that is bought)
Will you pay for the drinks?
You weren’t polite to me last night.
Prevent somebody from doing something
She prevented me from entering her room.
Nobody knows the reason for the accident.
She was pretty rude to me last night.
Run into (= meet)
I ran into James at the library this morning.
Shocked at / by
I was shocked at / by the news of her death.
Sorry about something that has happened
I am sorry about your accident.
Sorry for / about something that one has done
I am sorry for / about interrupting you.
Sorry for a person
I really feel sorry for her.