- either1. pronunciation.The pronunciations iy-dhǝ and ee-dhǝ are about equally common.2. parts of speech.Either functions in two ways: as an adjective or pronoun, and as an adverb or conjunction. In all these uses, it means essentially ‘one or other of two’; when more than two alternatives are involved an alternative word (such as any) or construction is often needed, at least in more formal contexts. (This aspect is discussed further in section 3 below.)a) adjective and pronoun. Either means ‘one or the other of two’ (Either book will serve the purpose / Either of you can go) or ‘each of two’ (We sat down on either side of the table).b) adverb and conjunction. The basic meaning is ‘as one possibility or alternative’, and is normally balanced by or (You may have either tea or coffee / Either come in or go out, but don't just stand there). The position of either and or should be such that the grammatical structures are correctly balanced, as in Either I will go with John or I will stay here with you but not in ☒ Either I will go with John or stay here with you. It is also used with a negative, normally at the end of a clause or sentence (She didn't want to come, either / There is no time to lose either).3. either with more than two.The essential duality of either is shown by the following example:
• We either rely on our children to translate for us or we can try to catch up —Illustrated London News, 1980.If the number of alternatives is extended to more than two, opinion is divided about the elegance and even the acceptability of the results; in general a greater tolerance is necessary in conversational English, but in formal English it is advisable to restrict either to contexts in which there are only two possibilities. In the case of the adjective and pronoun use, either should be replaced by any when a choice from more than two is involved (Any of the books will serve the purpose). It should be noted, however, that any can mean one or more than one, and so any one should be used when this is the meaning (Answer any one of the following three questions).4. singular or plural after either.Normally either governs a singular verb (Has either of you seen my pen? / Either John or Peter has got it), but with the type either of (+ plural) a plural construction is sometimes used to emphasize the plurality of the statement as a whole, especially in inverted questions when the verb comes first
• (Have either of you two ladies received an anonymous letter? —A. E. W. Mason, 1924).Notional and grammatical agreement are in conflict in informal uses such as Either John or Jane avert their eyes when I try to take their photograph. When one of the alternatives is singular and the other plural, normal usage is to make the verb agree with the one closer to it (Either the twins or their mother is responsible for this). See also neither.
Modern English usage. 2014.