I knocked on the door but ________ answered.
It’s easy to _____ this math problem. A. work out B. find out C. look out
Japan is ________ the east of China. A. in B. on C. to
The traffic sign “ ” means “__________”. A. go B. stop C. danger
—Would you like to go with me?—I’d like to, _________ you don’t want to go alone. A. until B.if C.after
—Would you help me plan a trip? —_________________ A. You bet! B. Yes, I can. C. Not at all.