Thetimewillcomemancanflytoouterspacefreely.A.thatB.whenC.inwhichD.which可是答案为什么选C呢?

Question

The time will come ______ man can fly to outer space freely.
A.that B.when C.in which D.which
可是答案为什么选C呢?

Answer 1

The time will come ______ man can fly to outer space freely.
A.that B.when C.in which D.which
选择B.
人类可以自由飞向太空的时期就要到来了.