|either = one OR the other||Would you like tea or coffee? ∼ Either; I don’t mind.|
(= ‘You can give me tea OR coffee; I have no preference.’)
|neither = not one and not the other||Would you like ham or beef in your sandwich?|
∼ Neither; I’m a vegetarian.
(= ‘I don’t want ham and I don’t want beef.’)
|both = the first AND the second||I take both milk and sugar in my coffee.|
(= ‘I take sugar. I also take milk.’)
|We use either with a singular noun.|
We use either of with a plural noun.
We use a singular verb with either and either of.
either of the cars
Either day is fine for me.
Either of the days is fine for me.
|We use neither with a singular noun.|
We use neither of with a plural noun.
We use a singular verb with neither and neither of.
neither of the houses
Neither day was suitable.
Neither of the days was suitable.
|We use both with a plural noun.||both houses|
both of the houses
Both (of) my brothers are tall.
|We use of before the pronouns us, you, them.||both of us, both of you, either of them, neither of them, etc.|
|Between of and a noun we use these, those or my, your, John’s, etc., or the.||both of those houses, neither of my brothers, both of John’s sisters, either of the cinemas|