It's good for you to keep ______ when you have something difficult _____
A. trying; to do
B. trying; doing
C. to try; to do
D. trying; to be done
应该选择哪个，A还是D，百度一下，有的说A有的说应该是D。
孩子说是D，但答案是A。请高手帮忙，并说明一下原因。谢谢。
作者: 悠悠 时间: 2014-4-13 16:27
根据过去学习的语法知识，difficult to do是固定搭配，句子就是这么说的。不知道怎么解释可以跟清楚些，抱歉啦。作者: seawhirl 时间: 2014-4-13 20:10
这个题牵涉到不定式与前面所修饰名词的搭配关系。不定式修饰前面的名词作后置定语，存在以下几种关系：
1. 主动关系：不定式与所修饰名词是主动关系，即名词是不定式结构的逻辑主语。
如：
He was the last one to arrive (=who arrived)
Have you got the key to unlock the door (=that can unclock the door)?
2. 动宾关系，即名词是不定式结构的逻辑宾语。
如：
He has a large family to support (=he must support )
This is the last book to read (= that we can read).
3. 同位关系
I had no wish to quarrel with you.
He hit back the urge to tell a lie.
作名词后置修饰语的不定式可以采取主动态，也可以用被动态。有时两种语态均可采用，意义上无甚区别。
Give me a list of people to invite/ to be invited.
There is no time to lose/ to be lost.
但在有些情况下，用主动态比用被动态自然，如：
I’ve got letters to write.
We’ve got a lot of cases to investigate.
另外一些情况下，又以被动态为妥，如：
The cases to be investigated are not to be made public in press.
The question to be discussed at the next meeting will be hard nut to crack.
you have something difficult to do. 句中主语是you, 也是do 这个动作的发出者，所以用主动语态。
如果换成被动语态，句子就成了这样的：
you have something difficult to be done. 意味着你要别人去做困难的事情，而不是自己去做；也就是说句中主语you 不是do这个动作的发出者，而是have这个动作的发出者。根据上下文，显然不合题意。作者: beibei581 时间: 2014-4-14 09:42
A
keep trying 继续反复努力尝试 sb have sth to do 要去做某事作者: beibei581 时间: 2014-4-14 09:42
A
keep trying 继续反复努力尝试 sb have sth to do 要去做某事作者: liumimi 时间: 2014-4-14 11:01
A。
keep doing sth, have sth (difficult) to do 作者: txltree 时间: 2014-5-16 08:59
选A。我认为第二空主语为人，所有用主动。作者: imlucky 时间: 2017-7-17 16:48
