make more progress,___.

问题描述:

make more progress,___.
To make more progress,_______.
A.one must work hard
B.working hard is needed
C.what you need is to work hard
D.what one needs is to work hard
我知道是选A,但是想问为什么

很高兴为你解答: 必须主从一致,虽然前面没表明主语,但是说的是去取得进步,主语肯定是人,后面主语也要是人,就是A.