His example（）that everyone can become a useful person in society so long as he is willing to work hard.

A.expresses

B.thinks

C.indicates  

D.supplies

电晕线放电性能好是指（）。

A.起晕电压低；

B.伏安特性好；

C.对烟气条件变化的适应性强；

D.起晕电压低，伏安特性好，对烟气条件变化的适应性强。