— Is it my age ________the boss minds?
—I’m afraid so. He will consider ________ necessary to have an experienced assistant.

which；it

that；it

which；that

that；that

考查强调句型和it的用法。第一空that与it is构成强调句型。第二空it是一个形式宾语，真正的宾语是不定式to have an experienced assistant，选B。

Like other animals, we are          until we know it is safe to relax.

on purpose

on fire

on guard

on duty

考查介词短语辨析。句意：像其他动物一样，我们在知道安全的时候才放松警惕。A.on purpose 故意；B. on fire着火；C.on guard 警惕；D.on duty值班。结合后文we know it is safe to relax，可知我们在知道安全的时候才放松警惕。故选C项。

As crossing

While you cross

While crossing

Cross

这题考查时间状语从句的省略式，当主从句的主语一样时，可以省略从句的主语和be动词，这题的while crossing就省略了you are，句意是：当你过马路时，别忘了两边看看。选C。

It is said that railway station is now         large as What it was.

as twice

twice as

twice much

much twice

考查倍数表达法。句意：据说火车站现在是原来的两倍大。倍数的基本结构一般为“A+倍数+as+形容词或副词的原级+as+B”，表示“A正好是B的多少倍”。联系下文large as，此处用twice as large as 表示“是.....的两倍大”。故选B项。

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。