both的用法

Both：adj. 两个的，两者的
adv. 并，又，两者都
pron. 双方都，两者都
conj. 既…且
①both表示两者都…，有多种词性。

例：
副词：We are both students.
代词：The brothers are good at playing basketball. Both will take part in the game. 形容词：Both (the) instruments are valuable to this process.
连词：Both copper and silver are good conductors of electricity.
铜和银都是良好的导电体。

②它的否定形式是neither，词性和both一样，例：
We are neither student.
Neither of us is a student. = Either of us is not a student.
③Both可以和名词、代词连用，也可以和动词连用，在句子中做主语、宾语及同位语，也可以做定语。

1）both和名词、代词连用
both + (of) +the/物主代词/指示代词/ + 名词
Both of the cats are asleep.
I bought both of these bottles in China two years ago.
Both of his daughters are doctors.
在人称代词前一定要用both of，不能说both we, both us, 但可以说us both, them both.
Both of us like skating,
I want both of them.
2）both直接修饰名词，不加of
Both children won prizes.
注意：不能说both of children，可说both of the children
I’ve got oil on both hands.
注意：不能说both of hands, 可说both of my hands.
④当both在句中作主语的同位语时，也可以与动词连用，both在句中的位置通常用于be动词、助动词或情态动词之后，实义动词之前。

1）放在be动词之后
The children are both lovely.
They are both from Australia.
注意：在感叹句或者简略答语中，both应该置于be之前。

How beautiful they both are!
--Are you both from Japan?
--Yes, we both are.
2）放在行为动词前
We both like watching TV.
They both want to go shopping.
3）当谓语动词是由几部分组成时，both要放在第一个助动词后面We have both studied acting.
The rooms have both been cleaned.
⑤both做代词，可单独使用，其后不接名词
The brothers are good at playing basketball. Both will take part in the game.
--Which one do you want?
--I'll take both please.
注意：both与not连用，是部分否定
Both the doors are not open.
⑥both…and…两者都，能连接各种并列成分。

Both Mary and Tina are girls. (连接两个主语)
If you are success, you can get both money and power. (连接两个宾语)
These books are both interesting and helpful. (连接两个表语)
It is necessary to build a lot of petrochemical works, both because of China is rich in petroleum and because there is a great demand for petrochemicals. (连接两个状
语从句)。