Neither = not either of two things or people
Either = any one of two

1. Neither

We use NEITHER or NEITHER OF to make a negative statement about two people or things. There is no difference in meaning. It takes a singular verb. For more than two we use NONE; e.g.

Neither parent went to the club.
= Neither of the parents went to the club.

NOTE: We don’t use BOTH to make a negative statement for two, we use NEITHER OF; e.g.

INCORRECT: Both of these shirts aren’t dry yet.
CORRECT: Neither of these shirts is dry yet.

2. Either

We use EITHER or ‘EITHER OF’ to make a choice between two possibilities. You use EITHER before a singular countable noun, and EITHER OF before a plural pronoun or before a plural countable noun having an adjective. There is no difference in meaning. It takes a singular verb; e.g.

You can take either watch.
= You can take either of the watches.

They didn’t want either child to know about this.
= They didn’t want either of the children to know about this.

I don’t know either of them.

INCORRECT: I don’t like either pens.
CORRECT: I don’t like either pen. OR I don’t like either of the pens.

NOTE-I: ONE OF & EITHER OF

When we talk about two or more people or things and there is no idea of a choice, we use ONE OF (not EITHER OF); e.g.

INCORRECT: Either of your parents has beaten him.
CORRECT: One of your parents has beaten him.

INCORRECT: Either of their daughters has just had a baby.
CORRECT: One of their daughters has just had a baby.

NOTE-II: EITHER cannot be the subject of a negative verb. However, it can be subject or object of an affirmative or interrogative verb; e.g.

INCORRECT: Either will not serve well.
CORRECT: Neither will serve well.

For more chapters/topics on English Grammar read the following book authored by me.

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For English Practice Sets on various topics read the following book authored by me.

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