---Shall I tell Jhon about it?

---No, you            . I've told him already.

needn't

wouldn't

mustn't

shouldn't

考查情态动词。句意：---要我告诉约翰这件事情吗？--不，不必了，我已经告诉他了。A.needn't不必；B. wouldn't不会；C. musn't禁止，不允许；D. shouldn't 不应该。根据“I've told him already”，可知这里是“不必要”。故选A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。

When           another country, you should be aware of those differences and respect them.

visit

to visit

visiting

visited

考查非谓语动词。句意：当拜访另一个国家时，你应该知道这些不同之处并尊重它们。分析句子可知，空格处应填非谓语动词和when一起构成时间状语，逻辑主语you和visit之间是主动关系，应用现在分词。故选C项。

There                   in the world              China is a great country with a long history and rich culture.

are no doubt; that 

are not doubts; if

is no doubt; that

is not doubt; if

考查固定句型和同位语从句。句意：毫无疑问，中国是世界上有着悠久历史，丰富文化的一个大国。分析句子可知，这个句型为 there is no doubt that 引导，表示“毫无疑问......”.本句为that that 引导的同位语从句，句意和句子结构完整。故选C项。

Every evening after dinner, if not ________ from work, I will spend some time walking my dog.

being tired

tiring

tired

to be tired

考查省略句。当状语从句的主语和主句主语一致，且状语从句中有be动词的时候，可以把状语从句的主语和be动词一起省略，本题if后面省略了I am，句意：每天晚上吃完晚饭以后，如果不是很累，我就会花点时间来遛狗。故C正确。

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

The law           equal rights for men and women.

permits

confirms

persevers

guarantees

考查动词辨析。句意：这个法律确保了男女权利平等。A.permit允许；B.confirm证实，证明；C.persever坚持；D.guarantee保证，担保。分析句意可知，空格处为动词做谓语，其主语为the law,为单数则谓语动词用第三人称单数形式。又因the law作用是保证公平。故选D项。

        bothers me is that I can't keep my mind on the task, but on personal gains or losses.

What

It

That

One

考查主语从句连接词。句意：困扰我的是我不能专注于任务，而是专注于个人得失。此处为主语从句，从句中缺少主语，结合句意表示“困扰我的是”应用what。故选A项。

It was last night ________ I saw the comet.

the time

when

that

which

强调句的结构是：It＋be＋强调部分＋that(who)＋主谓句。强调句的连词只有两个，that和who。当强调的部分是人，且为句子的主语时，才用“who”，其余用that。因此选C。