Each与every都有“每个”的意思,但二者含义及语法功能不同,主要区别是：
1.each既可用作形容词,又可用作代词,在句中可以作定语,主语、宾语、同位语、状语等.例如：
Each student has his own dictionary .（形容词,定语）
每个学生都有自己的字典.
Each has his good point .（代词,主语）
各人有各自的优点.
Our headteacher had a talk with each of us .（代词,宾语）
我们的班主任与我们每个人都谈了话.
The students each have a desk .（代词,同位语）
学生们每人有一张书桌.
The children can have a bag each .（副词,状语）
孩子们每人可带一只提包.
2.each与every都可用作形容词,在句中作定语,但each更强调个人或个别,every更强调全体或全部.比较：
I know each number of your family .
我认识你们家的每个成员.
I know every number of your family .
我认识你们家的每个成员.
3.each指两个或两个以上的人或事物中的“每个”；every是指许多人或事物的“全体”,与all的意思相近.试译：
这条街上每边都有很多商店.
〔误〕There are many shops on every side of the street .
〔正〕There are many shops on each side of the street .
我给她父母每人一件礼物.
〔误〕I gave a present to every one of her parents .
〔正〕I gave a present to each of her parents .
4.指上下文提到过的确定数目中的“每一个”时,要用each；如果上下文没有提及时,不能用each,要用everyone等.试译：
我认为这三个答案个个都正确.
〔误〕I think every answer of the three is right .
〔正〕I think each of the three answers is right .
我看见人人都忙着工作.
〔误〕I saw each was busy with his work .
〔正〕I saw everyone was busy with his work .
5.each 单独作主语或each、every修饰的单数名词作主语时,谓语动词为单数形式,但each of them作主语时,谓语动词用单数或复数形式都可以.例如：
Each / Each person / Every person is living a happy life now .
人人都过着幸福生活.
Each of them are / is wearing full dress .
他们个个都身着盛装.
6.every可以与not连用构成部分否定,意思是“并不/非人人”,而each则不可以与not连用.全部否定是no one ,意思是“个个都不”、“没有人”等.例如：
人人都不喜欢这个电视剧.
〔误〕Each / Everyone / Every one of them doesn’t like the TV play .
〔正〕No one likes the TV play .
7.each与other可构成相互代词,every则不可以.例如：
We should take care of each other and help each other .
我们应该互相关心,互相帮助.
8.表示“每隔……”、“每……”,要用“every＋基数词＋复数名词”.这种结构中的every不能用each替代.例如：
They’ll choose one out of every ten girls .
他们将在每十个姑娘里挑选一个.
We hand in our homework every three days .
我们每隔两天（每三天）交一次作业.
注意：“每三天或每隔两天”,也可以写作“every third day”,即,若用序数词时,后接单数名词.再如every four weeks / fourth week（每四周/每隔三周）,every other day / second day / two days（每隔一天）,every other line（每隔一行）等.
摘自《语数外学习》