Look! A crowd of people over there. Go and see what ________ and if it is a bargain, take it.
I delayed _______ your letter because I had been away for a week.
.If he succeeded _______ a job, his children wouldn't be suffering from hunger now.
I still remember _______ to my home town when I was young.
The old sick lady entered the hospital, ______ her two sons.
_______ many times, he still couldn't understand.