.Some people say more but do less others do the opposite.A. onceB. whenC. whileD. as

问题补充：

.Some people say more but do less others do the opposite.

A. once

B. when

C. while

D. as

答案：

A. once

B. when

(答案→)C. while

D. as

解析：词义辨析题。While表示两者进行对比，“然而”，句意：有些人说得多做得少而有些人正相反。