teacher should set a good example heir students,because what they do and say has a great effect

问题描述:

teacher should set a good example heir students,because what they do and say has a great effect
them
A:for;to B:to;on C:for;in D:to;to

B
set example to 给某人树立榜样,也可以用for.
have effect on sb/sth 对什么有影响