______,the spaceman saw the Great Wall of China.
问题描述：
______,the spaceman saw the Great Wall of China.
A.While flew in the spaceship
B.While flying in the spaceship
C.If flew in the spaceship
D.To fly in the spaceship
答
应该选B,While（he was） flying in the spaceship,the spaceman saw the Great Wall of China.句子省略了he was.A.While flew in the spaceship,应该用正在进行时态,排除.C.If flew in the spaceship（正确应该是If...那为什么要用进行时呢？？？？要正在飞行，才能看到长城。所以用进行时态例如：While( he was )walkingtoschool,hesaw a small dog on the road .那后面那个看见长城怎么不用进行时强调的是看得见，而不是一直在看。