It is difficult to tell exactly ____ the saying began, but it is probable that it was in the theater or movie industry.
14. Be quiet, kids. You’ll have to wait ______ your names are called.
The path to dreams may not be smooth and even at great cost, but ______ on to them.
I dislike those programs ______ viewers call in to talk about their private problems.
The hotel turned us down because we didn’t make reservations, but we ______ have.
Home-working opportunities and ______ working hours are top concerns for the working mothers.