几道高二英语题目,拜托各位

几道高二英语题目,拜托各位
1、When__help,one often saysThank youorIt's kind of you.
A、offering B、offered C、to be offered D、to offer
2、—What do you think made Mary so happy?
--___the final examination.
A、As she passed B、Because she passed
C、Passing D、Because of passing
3、___do we go for picnics.
A、Certainly B、Sometimes C、Once D、Seldom
4、The town is so called just__a hero in the Anti--Japanese War named Zhao Shangzhi.
A、as a result of B、in case of
C、in honour of D、with the help of
PS:请各位在解答时尽量给出简略的解答过程,谢谢各位!

1、B、offered
过去式表示被动,是被帮助时说Thank youorIt's kind of you
2、C、Passing
注意疑问词为What,而不是how.可翻译为是什么使他高兴,用passing动名词
3、D、Seldom
Seldom 使句子倒装,从而出现了do
4、C、in honour of
意思为纪念,A为是什么的结果,B是照顾到,D是在他的帮助下