Tens of thousands of trees _____ in the area in the past few years.
A. have been planted B. were planted C. have planted D. had planted
— I'm wondering why the visitors chose to stay with the host family.
— _____real local life.
A. Experiencing B. Experience C. To experience D. Having experienced
How long do you think it will be _____ we can find a new water source?
A. after B. before C. when D. since
High up in the mountains _____ a quiet small village, with only 20 households.
A. surrounds B. locates C. lies D. lays
A heavy snow promises a good harvest, _____ is often the case.
A. where B. as C. that D. what
After his wife died, he kept himself _____ from other people and the outside world,
A. set off B. cut off C. put off D. taken off
