8下英语 He gave each boy an apple.为什么是each

如果要想了解EACH的用法.必须比较着看
each both either neither
both:两个都(用于肯定)
each:每个(表个体)
Every:每个(表全体)
neither:两个都不(用于否定)
either:1).或者(用于选择)常与or 连用
2).也(表相同)(用于否定)
e.g.:
1.Both the students are girls.
2.Each student has a pen.
3.Neither the student is from London.
4.Either he or she has a pen.注：has是被she 限定的,意思就是说,动词的形式与or 后面的主语一致.
例如,Either he or I have a pen.
He doesn't have a pen,she doesn't have,either.
（1）each具有名词和形容词的功能.
（2）each指两个或两个以上的人或事物中的“每个”.：
He gave a book to each of his parents.
他给他父母各送了一本书.
（3）each作为形容词,修饰单数名词,接单数动词.作为代词,单独使用,接单数动词；放在复数名词和代词后作同位语,接复数动词.each of them后可接单数或复数动词.如：
Each man carries his own bag.（修饰单数名词）各人背自己的包.
We each have our own office.(作We的同位语)我们各有各的办公室.
Each carries his own bag.(代词)各人背自己的包.
Each of them are/is here.(代词)他们每个人都在这儿.
（4）代表each的物主代词可以用his,也可以用their.如：
Each carried their/his own bag.各人背他们/他自己的包.

强调个体，一个一个~

each 每个男孩。他给每个男孩一个苹果。没问题。