Small sailboats can easily turn over in the water ________.

if not managed carefully

if are not managed carefully

unless not managed carefully

unless are not managed carefully

While we may not be born with a nature talent, we can          for it with hard work.

break up

take up

bring up

make up

考查动词短语辨析。句意：虽然我们可能没有与生俱来的天赋，但我们可以通过努力工作来弥补。A. break up打碎；B.take up 拿起，开始从事；C.bring up提出；D. make up 弥补。根据上文we may not be born with a nature talent可知没有与生俱来的天赋，所以要通过努力工作来弥补。故选D项。

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。

The student completed this experiment to make come true         Professor Joseph had said.

that

what

when

where

考查名词性从句。句意：为了使约瑟夫教授所说的成为现实，这个学生完成了这个实验。        Professor Joseph had said作make的宾语从句，该从句中，空格处在从句中作said的宾语，表示“......所说的话”，因此应用what 引导该从句。故选B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。

I_____you can finish the exam in two hours.

does believe

do believe

did believed

do believed

句意：---我确实相信两个小时内能完成考试。这里用来强调，在谓语动词前加助动词do表示强调。句子的主语是第一人称，所以位于动词不能用单数，故排除A；did后用动词原形；do后用动词原形，故选B。

You don't have to know the name of the author to find a book. You           find the book by the title.

must

need

can

would

考查情态动词辨析。句意：你不需要知道作者的名字就能找到一本书。你可以按书名找到这本书。A.must必须，一定；B.need 需要；C. can可能；可能；D.would愿意。根据句意可知，此处表示一种客观的可能性，应使用情态动词can。故选C项。