You use either in front of the singular form of a countable noun to say that something is true about each of two people or things.
Instead of using either, you can use either of with a plural noun. For example, instead of saying 'Either answer is correct', you can say 'Either of the answers is correct'. There is no difference in meaning.
You use either of in front of plural pronouns.
Be Careful!
Don't use either without of in front of a plural noun or pronoun. Don't say, for example 'He was better dressed than either us.'
Some people use a plural form of a verb after either of and a noun phrase. For example, instead of saying 'I don't think either of you is wrong', they say 'I don't think either of you are wrong'.
This use is acceptable in conversation and in less formal writing, but in formal writing you should always use a singular form of a verb after either of.
You can use either or either of in a negative statement to emphasize that the statement applies to both of two things or people. For example, instead of saying about two people 'I don't like them', you can say 'I don't like either of them'.
If there are things on either side of something or either end of something, they are on both sides or both ends.
When one negative statement follows another, you can put either at the end of the second one.
| Adv. | 1. | either - after a negative statement used as an intensive meaning something like `likewise' or `also'; "he isn't stupid, but he isn't exactly a genius either"; "I don't know either"; "if you don't order dessert I won't either" |