21.Some students preferred to stay in the toilet ____ do morning exercises.
A. in order to not B. in order not to C.in not order to D.not in order to
22. Please ______ the numbers and I’m sure they will _______ more than 100.
A. add up ;add B.add up ;add up C.add up ;add up to D.add to;add up to
23.The teacher asked the boy _________.
A.what the matter was B.what was the matter
C.what the matter is D.what is the matter
