She is very hard-working,_______ he is very lazy.应选什么?为什么?
问题描述：
She is very hard-working,_______ he is very lazy.应选什么?为什么?
A.while B.when C.as D.if
答
A
意思是她很勤奋,而他却很懒惰.
while 表示转折和对比.