118.Greater efforts to control the population must be made if food shortage __________ avoided.A.is to be B.can be C.will be D.has been is to be

118.Greater efforts to control the population must be made if food shortage __________ avoided.A.is to be B.can be C.will be D.has been is to be
118.Greater efforts to control the population must be made if food shortage __________ avoided.
A.is to be
B.can be
C.will be
D.has been
is to be

118.Greater efforts to control the population must be made if food shortage __________ avoided.A.is to be B.can be C.will be D.has been is to be
将来时的被动语态
如果要避免粮食短缺,就一定要付出更大的努力来控制人口.

a,
如果要避免粮食短缺的发生,需要对控制人口实施更大的努力.

选A。如果要避免食物短缺，必须努力控制人口。