It has been warned that        to the surroundings with people infected by Covid-19 without any

protection can lead to severe result.

being exposed

exposed

having exposed

to expose

考查非谓语动词。句意：有人警告称，在没有任何保护措施的情况下，暴露在有感染 Covid-19的人环境中会导致严重的结果。分析句子结构可知expose在句中应用非谓语动词形式，表示“暴露”短语为be exposed to,且从句中缺少主语，expose 与主语people是被动关系，故应用动名词的被动式作主语。故选A项。

Tom looks so pale today. He ______ ill.

must be

had to be

should be

shall be

[翻译]汤姆看起来脸色不好，他一定生病了。[解析] A 试题解析：情态动词must表示推测。题目中表示肯定的推测。

I would really appreciate       if you can make time in your schedules to attend my lecture today.

that

it

this

one

考查形式宾语。句意：如果你今天能从日程安排中抽出时间来听我的讲座的话，我将不胜感激。I would appreciate it if/when...如果/当...时，我将非常感激。it 做形式宾语。故选B项。

How I wish every family         a large house with a beautiful garden!

has

will have

had

had had

考查虚拟语气。句意：我多么希望每个家庭都有一个带着美丽花园的大房子！此句是wish 引导的从句，从句要用虚拟语气，根据wish 可知是与现在事实相反，从句一般用过去时。故选c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。

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。

We played well, but I felt the team were            by one member, who didn’t try his best on the court.

let down

turned down

picked up

cheered up

考查动词短语辨析。句意：我们打得很好，但我觉得有一个队员在场上没有尽最大努力，让整个球队失望了。A. let down 使失望，放下；B. turned down 拒绝，调小；C. picked up捡起，接；D. cheered up使兴奋，振奋。结合句意可知，“有一个队员在场上没有尽最大努力”，所以“我们”感到失望。故选A项。