The time and effort he has devoted during the past few years ______ trees in that remote area is now considered to be of great value.
#95651
A
plant
B
planting
C
to plant
D
to planting
推荐题目
I always regret not         harder when I was young .
#97664
A
studying
B
having studied
C
to study
D
to have studied
—Can I smoke here?—Sorry.We don’t allow_______here.
#98519
A
people smoking
B
people smoke
C
to smoke
D
smoking
These clothes are very dirty.They need ___.
#97759
A
washing
B
to wash
C
wash
D
washed