If you work hard like this, you will           sooner or later.

give out

break up

break down

fall down

考查动词短语。句意：如果你继续这样辛苦工作的话，你迟早垮掉。A.give out分发 ；B.break up打碎；C.break down垮掉；D.fall down 跌倒。根据句意可知break down符合语境。故选C项。

True happiness does not            the possession of money, but the joy of achievement.

contribute to

lie in

result in 

add to

考查动词短语辨析。句意：真正的幸福不在于拥有钱，而在于成功的喜悦感。contribute to有助于；lie in 在于；result in 导致；add to增加。结合语境可知，此处指“真正的幸福不在于有多少钱”。故选B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。

Jenny was very sad over the loss of  the photos she had shot in Canada,          this was a memory she especially treasured.

as

if

when

where

考查连词辨析。句意：珍妮对失去她在加拿大拍摄的照片感到非常悲伤，因为这是她特别珍视的记忆。as 引导原因状语从句，表示“由于”；if“如果”；when“当......什么时候”；where“在哪里”。根据句意，前后文是因果关系，故选A项。

The most important promises we must keep are          we make to ourselves.

ones

those

these

them

考查代词。句意：我们必须遵守的最重要的承诺就是我们对自己做出的承诺。A. ones泛指上文提到的可数名词复数；B. those特指上文提到的可数名词复数；C. these这些；D.them他们。分析句子可知，为we must 是定语从句，修饰The most important promises，是句子的主语；be动词后缺少表演，we make to ourselves是定语从句，修饰空格处。根据句意，此处指上文提到的promises,由定语从句修饰表示特指，故用 those。故选B项。

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。