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。

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。

They elected him          captain of the team for         second time.

the; a

a; the

a; a

/; a

考查冠词的用法。句意：他们再次选他当队长。职位，官衔前面不加冠词，a second time表示“又一次，再次”；the second time表示第二次（顺序）。故选D项。

According to Professor Johnson, we don't have to read the book if we don't want to, as it is              .

worthwhile

necessary

optional

serious

考查形容词词义辨析。句意：根据约翰逊教授的说法，如果我们不想读这本书，就不必读，因为它是可选择的。A. worthwhile值得的； B. necessary 必要的；C. optional 可选择的；D. serious 严肃的，认真的。根据“  we don't have to read the book if we don't want to”可知，这本书读不读都可以，由此可知它是“可选择的”。故选C项。

---Miss Yuan，you promised！

---Well，______.But it was you broke your word first.

so was I

so did I

so I was

so I did

考查强调句。句意：袁女士，你承诺过的！噢，我确实如此。但是是你先失言的。A和B是一类回答，C和D是一类回答。当别人说他自己怎么样，而你有跟他同样的情况时，用AB这样的形式回答。当别人说你怎么样，而你自己也确实是他说的那样时，用CD回答。至于用be动词还是do要根据具体语句定，谓语是be时就用be的相应形式，谓语是实意动词时就用do的相应形式。根据句意，故选D。

          is a pity           you didn't attend the lecture last night. It was wonderful.

What; that

It; that

What; why

It; why

考查固定句型。句意：很遗憾，你昨晚没去听讲座。那太美妙了。此处为句型“It is a pity that.....”，表示“遗憾的是....", It 作形式主语，that 引导主语从句是真正的主语，从句句意完整，成分齐全，that不做成分，仅起引导作用。故选B项。

Your       as a student will be excellent if you develop a habit of reflecting on how you learn.

operation

growth

performance

character

考查名词辨析。句意：作为一名学生，如果你养成课后复习的好习惯，那么你的表现就会很优异。A.operation 操作； B. growth生长；C. performance 表现；D.character性格。学生如果有课后复习的好习惯，会表现优秀。故选C项。