this is ____ ,so we must ____ on it.A.a hard work;hard work B.hard work;work hard

问题描述:

this is ____ ,so we must ____ on it.A.a hard work;hard work B.hard work;work hard
C.hard work;hard work D.a hard work;work hard

B.hard work; work hard
后半个句子需要一个动词,这又B和D符合.
hard work前面不加a,所以只有B对