Suddenly a good idea occurred to her, but she couldn't find any paper           .

 to write

to write on

written

writing on

考查了非谓语动词。句意：她突然有了一个好主意，但是她找不到纸来写下它。根据句意可知，这里用不定式表目的，而且固定搭配是write sth on the paper。故选B项。

She reading

She reads

To read

Reading

考查时态以及省略。句意：—Joan正在做什么？—在房间里看报纸。根据句意说明描述的是现在正在发生的事情，所以使用进行时的时态，是对what is Joan doing?的回答。回答完整应该是she is reading...，此处省略了she is，故D正确。

A study shows the students who are engaged in after-school  activities are happier than        who are not.

ones

those

these

them

考查代词。句意：一项研究表明，参加课外活动的学生比不参加课外活动的学生更开心。空格处代词与the students是对应关系，可以用the ones 或者those替代。“them”指代前面提到的复数名词，不能与the students形成对应关系，“these”一般不用定语从句修饰。故选B项。

Though ____ the dangers of smoking to their health, smokers still find it hard to give up smoking.

aware of

are aware of

be aware of

考查状语从句的省略：句意：虽然很多经常吸烟的人已经意识到抽烟对他们健康造成了很严重的后果，但是他们仍然发现很难戒烟。Though引导的让步状语从句是省略句，完整的句子是：though smokers are aware of the dangers of smoking to their health。当主从句的主语一致的时候，可以省略从句的主语和be动词，选B

 Is _______ three hours _______ the poor boy to come to school on foot?

it; that it takes

there; that it takes

there; when

it; that

考查强调句。强调句的结构为It’s + 强调部分 + that从句。本题强调时间状语three hours。句意：可怜的男孩步行到学校花了3个小时吗？故A正确。

it was at 10 pm yesterday______he came home from work.

that

when

which

what

考查强调句。句意：昨天晚上10点他下班回家。考查it+be+强调部分+that+句子，选A。

One of the man holds the view          the book said was right.

that

whether

what that 

that what

考查同位语从句及主语从句。句意：其中一个人认为这本书说的是对的。分析句子可知，the view后面接了一个同位语从句（     the book said was right.），从句句子成分齐全，应使用that 引导，连接词在从句中不做成分，无意义。在同位语从句中又有一个主语从句（     the book said），在主语从句中said 缺少宾语，应用what 引导，指代“......的（事情，东西）”。故选D项。