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

The exhibition           next Sunday will feature paintings created by contemporary artists.

hosted

being hosted

to be hosted

hosting

考查非谓语动词。句意：下星期举办的展览将展出当代艺术家的作品。根据句意及分析句子结构可知，此处表示将来发生的事情，应使用不定式作定语，host 与 exhibition 之间是逻辑动宾关系，应使用不定式的被动式。故选C项。

Going on a trip into         space must be quite         exciting experience.

/; the 

/; an

the; the 

the; an

考查冠词。句意：太空旅行是令人兴奋的经历。第一空不填，space前面不加冠词，第二空后面的experience作“经历”时是可数名词，表示“一次令人兴奋的经历"。exciting首字母的发音为元音音素，因此应填an。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。

Why don't you             ? Try to make it a win-win situation for you both.

compromise

object

salute

rate

考查动词词义辨析。句意：你为什么妥协呢？试着为你们双方创造

双赢的局面。A.compromise妥协；B.object反对；C.salute致敬；D.rate比率。由后文试着为你们双方创造双赢的局面，可知前面讲的是妥协。故选A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。

When it comes to modern communication, network safety is always a major          . 

concern

advantage

opportunity

solution

考查名词辨析。句意：当涉及现代通信，网络安全一直是一个主要令人担忧的问题。A. concern关心，令人担忧的事实或情况；B. advantage 优势；C. opportunity 机会；D.solution解决方案。网络安全一直是现代通信的个主要令人担忧的问题。故选A项。

The sunlight is white and blinding,           hard-edged shadows on the ground.

throwing

being thrown

to throw

to be thrown

考查非谓语动词。句意：阳光炽白炫目，在地上投下浓重的阴影。主语The sunlight和throw是主动关系，因此要用现在分词表主动，此处是现在分词短语作状语。故选A项。