问题 有for five years为什么用过去时呢

—Does your sister work as a teacher in Canada? —No, but she once ______ there for five years． A．taught B．had taught C．has taught D．would teach改题答案为A,可不可以用完成时啊，谢谢！

问题 agree with sb that...结构分析

一个句子中，同时出现的agree的两种用法：She agreed with her parents and brothers that it would be... 在这个句子中同时包括了谓语agree 的两个用法。agree with SB（介词短语） 和 agree + that（从句）。 请问，是否这些在做及物动词时可以...

问题 step down as 的理解

...wn as chairman for three years after triggering an S EC investigation when she tweeded about taking Tesla private。我想这句话中step down是一个动词短语，后面紧跟的单词as是介词，但以前没有见过动词短语后面紧跟介词的使用，请帮助举出类似表达方式...

问题 双宾结构的句型由主动改成被动，原来的“直接宾语”还叫“直接宾语”吗

前后为主被动的两句话：主动：He gave her some money.被动：She was given some money by him.改成了被动语态后，some money仍然叫做直接宾语吗？但被动语态的句子中明明已经没有间接宾语了呀

问题 who is doing what是什么用法

看到这样一个句子：I don't know who's doing what.请问这里的 who's doing what 是什么用法？属什么语法现象？

问题 ​There is no talking loudly in public place.这句话对吗

公共场合不准大声说话。There is no talking loudly in public place.请问：这句话这么说正确吗?

问题 What you have done is spoilt...中的spoilt是过去分词还是过去式

What you have done is spoilt everything. 请问句子里面的 spoilt 是过去分词还是过去式？ 谢谢!

问题 A friend in need is a friend indeed的省略分析

a friend in need is a friend indeed请老师分析一下这个idiom， 或者把省略的部分补充完整。 因为我理解的意思是：需要帮助的朋友是真正的朋友，还有跟实际意思相反。

问题 说Sb is generous to do sth

generous 通常用于 It is generous of sb to do sth。如： It was generous of you to give us so much money. 你给我们这么多钱，真慷慨。 但是可以用于 sb is generous to do sth吗？比如下面这样改一下： You were generous to give us so much money. 你给我们这...

问题 sth is the trick to do和the trick to doing的用法

看到两个例句：The real trick to managing your money is not what you do — it’s how you do it. The main trick to use in any of these circumstances is the right set of keywords. 为什么一个是不定式一个是to做介词的动名词，这两个可以换吗？

问题 主谓一致疑问：More nurses is the next item on the agenda.

看到这样一个句子：More nurses is the next item on the agenda.不明白为什么用单词动词。

话题 It is kind of sb to do sth

话题 It is adj of sb to do sth

话题 It is not for sb to do sth

话题 It is foolish for sb to do sth