Whenhelp,oneoftensays"Thankyou"or"It'skindofyou."A.offeringB.toofferC.tobeofferedD.offered解释下为什么,有点明白了，可为什么when后面直接加被动呀？主语被省略了吧？

Question

When _____help,one often says"Thank you "or "It's kind of you."
A.offering
B.to offer
C.to be offered
D.offered
解释下为什么,
有点明白了，可为什么when后面直接加被动呀？主语被省略了吧？

Answer 1

选D
当状语从句的主语和主句主语一致时,可以把从句中的主语省略.这句话完整的应该是When one is offered help,one often says"Thank you "or "It's kind of you." 道谢的人肯定是被给予帮助所以用被动语态.
C项虽然也是被动,但不定式表示的是”将来“,这里是描述的一般情况,故用一般现在时的被动,表示经常发生的情况.
类似用法还可以说
She did an excellent job when given a chance.
She cried her heart out when shown the letter of her son.