In salad bars the waiter does not bring you salad. You have to____ yourself, usually to as much as you want.
________ mothers couldn’t go to the meeting, because they have gone to Shanghai .
Li Lei has been to __________ many times this month.
He is a success as a leader but he hasn’t ________ in teaching.
A classmate of _________ was here ten minutes ago.
A group of _________ are talking with two ___________.