It was along the Mississippi river _______ Mark Twain spent much of his childhood．

how

which

that

where

At that time they could not produce _______ computers, let alone high-grade ones．

normal

ordinary

popular

public

The _______ on her face told me that she was in a blue mood．

appearance

impression

attitude

expression

We always keep _______ spare bags with which we pack the rubbish．

a great many

the number of

too much

a great deal of

The World Wide Web is sometimes jokingly called the World Wide Wait because it _______ be very slow．

should

must

will

can

The English spoken in the United States is only slightly different from _______ spoken in England．

which

what

the one

that

I want to ring him _______ to know the reason why he rang _______ while I was speaking yesterday．

back; up

up; off

up; down

on; off

News came from the school office _______ Wang Lin had been admitted to Beijing University．

which

what

that

where

I have reached a point in my life _______ I am supposed to make decisions of my own．

which

where

how

why

If you are traveling ________ the customs are really foreign to your own，please do as the Romans do．

in which

what

when

where