1.词性功能与either：多种词性

①.限定词——名词前：

This is a long room with a door at either end

②.做代词——常接of：

Olive oil and corn oil are both suitable, so you could use either （of them）.

③.做副词——两个意思：

You can eithercome by bus or take a taxi.（either…or：或）

Jerry wasn’t there either.（=too/also也，用于否定和疑问句）

2.数量关系与either：辨别both；neither；not only…

Either…or; neither…nor;both…and; not only…but also这四组词都是在“两者之间”进行指代。不同的关键在于三点：

①.“全是”：both…and…;not only…but also…

The results of the research are both impressive andalarming.

There areproblems notonly with the students, but alsowith the teachers themselves.

②.“全否”：neither…nor…

The president spoke neitherfor nor against economic reform.

Neither his sonnor his daughter was at the funeral.

③.“之一”：either…or…

You can contact us eitherby phone, by email, or by letter.

When there’s a crisis, they eitherdo nothing or do something totally useless.

3.主谓一致与either：均按照“就近原则”，即以最接近谓语动词的为准。

Not only I but also Tom and Mary are fond of watching television.

Either he or you are right.

Neither the mayornor the council members haveyielded on the issue.

Neither the councilmembers nor the mayorhasyielded on the issue.

4.部分倒装与neither/notonly：最接近否定词的主谓倒装

Not only do the professors have their own ideas on the matter,but the students have theirs too.

Not only had the poor man been arrested but he had been sent to prison as well.

Bob can't go, and neither canI. If she doesn't want it, neither doI.

Neither does he know nor cares what happened