_______, or you’ll fail the exam.
A. Studying hard B. Study hard C. To study hard
We really don’t know _______. Could you help us?
A.how to do | B.what to do |
C.to do what | D.to do how |
—Will you please ________ do that? —OK, I won’t.
A.won’t | B.not | C.don’t | D.can’t |
We had fun ________ the robots do many different kinds of things.
A.to watch | B.watched | C.watching | D.watches |
The boss makes the workers ________ long hours every day.
A.work | B.to work | C.works | D.working |
—________ will you come back from your work, Dad?
—In about half an hour, dear.
A.How long | B.How often |
C.What time | D.How soon |