一、one的用法

one作替代词,相当于“a(an)+名词”。用来代替前面出现过的“同类”事物,one代替单数可数名词,ones代替复数可数名词,one不能代替前面的不可数名词。如:

1. I hope there are enough glasses for each guest to have ____.

A. it   B. those    C. them     D. one

2. —Why don’t we take a little break?

—Didn’t we just have____?

A. it   B. that     C. one D.this

3. Mr Zhang gave textbooks to all the pupils except ____ who had already taken them.

A. the ones         B. ones

C. some             D. the others

二、it的用法

it用作替代词,代替前面提到过的事物“本身”,而one代替前面提到过的“同类”事物。如:

1. The Parkers bought a new house but ____ will need a lot of work before they can move in.

A. they     B. it     C. one        D. which

2. Tom’s mother kept telling him that he should work harder, but ____ didn’t help.

A. he       B. which    C. she  D. it

it可作形式主语

当动词不定式、动名词或从句作主语时,通常把它们放在谓语之后,而用it作句子的形式主语。如:

____ is a fact that English is being accepted as an international language.

A. There  B. This   C. That   D. It

it可作形式宾语

当复合宾语中的宾语是不定式、动名词或宾语从句时,往往把宾语放在它的补足语后面,而用it作形式宾语,放在宾语补足语之前。如:

I hate ____ when people talk with their mouths full.

A. it   B. that     C. these    D. them

it可用于强调结构

要强调句子的某一成分(通常是主语、宾语或状语),常用的结构是“It is/was+被强调部分+that/who+句子的其余部分”。如果被强调的部分是人,可用who, whom代替that。如:

1. Was it during the Second World War ____ he died?

A. that             B. while    C. in which         D. then

2.It is the ability to do the job ____ matters, not where you come from or what you are.

A. one B. that     C. what     D. it

it可用于it doesn’t matter句型中。如:

Does____  ____matter if he can’t finish the job on time?

A. this     B.that C. he   D. it

三、that的用法

that作替代词,相当于“the+名词”,that与it一样,指前面所提到过的事物“本身”,that后可有of短语作后置修饰语,但it不可以。that既可代替前文出现过的单数可数名词,又可代替不可数名词。如:

—He was nearly drowned once.

—When was____?

—____was in 1998 when he was in middle school.

A. that; It         B. this; This

C. this; It         D. that; That