1 basic course
2 basketball game
3 bathing suit
4 be a mystery to someone
5 be/feel under the weather
6 be/run low
7 be about to
8 be absent from school
9 be absorbed in
10 be accustomed to
11 be acquainted with
12 be addicted to
1 be all in a day's work
2 be allergic to sth.
3 be amazed at
4 be attached to
5 be backed up
6 be behind the time
7 be behind schedule
8 be better off
9 be booked up
10 be bound for
11 be bound to
12 be burned up