Only after my friend came ______.

did the computer repair

he repaired the computer

was the computer repaired

the computer was repaired

句意：直到我的朋友来了之后电脑才被修理。放于句首的only修饰时间状语从句after my friend came，主句应进行部分倒装，将助动词was提到主语前面，故选C项。

It was not until 1920 ___ regular radio broadcasts began.

when

which

that

since

此题考查强调句。句意为：直到1920年，常规的电台才开始。这句话把it is/was和that去掉后，仍是完整的一句话，因此我们可以知道这是一个强调句，而且是对not...until“直到...才”的强调。结构是：it is/was+not until+其他成分。故选:C.

Dr.Rowan,           secretary resigned two weeks ago, has had to do all his own typing.

whose

of whom 

of which

which

考查定语从句。句意：罗文博士的秘书两周前辞职了，他只能自己打字。          secretary resigned two weeks ago是非限制性定语从句，修饰Dr.Rowan, 引导词在从句中作定语，表示“Dr.Rowan's”，表示“......的”，应用关系代词whose引导该从句。故选A项。

We shouldn't take         for granted that we still have a lot of time before the Entrance Examination.

this

that

it

such

考查代词。句意：我们不应该想当然地认为在高考前我们还有很多时间。这里涉及了一个固定句型take it for granted that 认为.....是理所当然的，该句型中it 作形式宾语，真正的宾语是后面that引导的从句。故选C项。

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。

If you want to catch the first bus you'd better         for the bus station immediately.

set up

set about

set down

set off

考查动词短语辨析。句意：如果你想赶上第一班公交车，你最好马上动身去车站。A. set up建立；B. set about开始做.....;C. set down 记下；D. set off 出发，动身。结合上文If you want to catch the first bus you'd better可知此处指“动身，出发”，应用set off。故选D项。

It was along the Mississippi River _________ Mark Twain spent much of his childhood.

how

which

that

where

此处构成It was...that...强调句式，句中强调了介词短语along the Mississippi River。故选C。