It is well-known that crack cocaine is a powerful             drug and users become           to it much more easily if they smoke it.

addicted; addict

addictive; addict

addicted; addictive

addictive; addicted

考查形容词辨析。众所周知可卡因是一种强大的令人上瘾的毒品，如果使用者吸了它更容易上瘾得多。addicted上瘾的，着迷的；addict"shi使沉迷；使上瘾”是动词；addictive “使成瘾的，令人沉迷的”。第一空表示“令人上瘾的”用addictive，故排除A，C项；become addicted to “对....上瘾”，第二空填addicted。故选D项。

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。

If you don't understand something, you may resrarch, study, and talk to other people          you figure it out.

because

though

until

since

考查连词。句意：如果遇到不懂的东西，你可以搜索、研究，和别人交流直到弄明白。A. 因为； B. 尽管；C.until直到；D.since自从，因为。根据句意可知，until符合语境。故选C项。

He punished the children          their carelessness         making them pay for the damage.

by; for

with; by

for; by

about; with

考查介词。句意：他因为孩子们的粗心惩罚他们赔偿损失。根据句意可知：“their carelessness"表示他们被惩罚的原因，需用介词for表原因。"making them pay for the damage"表示他们被惩罚的方式，需用介词by表方式。故选C项。

---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。

With a lot of difficult problems           ,he feels like a cat on  hot bricks.

to settle

being settled

settling

settled

考查非谓语动词。句意： 因为有一大堆难题要解决，他感觉像像热锅上的蚂蚁。本句with +名词+to do sth,动词不定式表示的动作尚未发生或当时看来尚未发生。本句表示“因为有一大堆难题要解决”。故选A项。

The number of deaths from a powerful typhoon sweeping across China’s east coast          to 30 on Sunday.

raised

rose

aroused

arose

考查动词词义辨析。句意：周日，异常席卷中国东海岸的强台风造成的死亡人数上升到30人。A.raised提升，增加； B.rose 增加（原形是rise）C.aroused激起，引起；D.arose发生，出现。分析句子可知，这里要表达“人数增长到30”，而A,B选项中，raise是及物动词，后面直接接宾语，而rise为不及物动词，用“rise to”表示“增长到.....”。故选B项。

Since this accident has nothing to do with him, he seems no way             .

to be blamed

to blame

blame for

to blame for

考查固定用法。句意：既然这次事故与他无关，他似乎也就无可指责了。短语sb to be blame“某人该受责备，某人应该负责”，为固定搭配，没有被动语态。故选B项。