—Do you enjoy________a volunteer?
—If you want ________this, you’d better join us.
A.being, knowing B.to be, knowing C.being, to know
Every year, more than 70,000,000 sharks ________ for their fins (鱼翅).
A.were killed B.have killed C.are killed
My sister and I________ to play with snow and make a snowman if it snows tomorrow.
A.go B.am going C.will go
—Could you tell me where you found Miss Gao just now?
—Certainly. In the principal's office. They ________ happily at that time.
A.are talking B.have talked C.were talking
—What do you often do at weekends?
—I often ________ my grandparents.
A.visit B.visited C.have visited
—Time flies! Nearly four years has passed since we ________ each other for the first time. How wonderful it is!
—Treasure the time we have!
A.meet B.met C.have met