Either/Or and Neither/Nor (Beware Double Negatives)

The Quick Answer
The pairing Neither/Nor plays a negative role, so take care to avoid an unintended double negative. For example:
  • He didn't find neither the map nor the key.
Neither is paired with nor and either is paired with or. You cannot mix them, but often the word either is omitted.

Either/Or and Neither/Nor (Beware Double Negatives)

The pairings either/or and neither/nor can be used to group two people or things. (Although not a major grammatical error, the grouping of more than two things is frowned upon by followers of some style conventions.)

Examples:
  • I could neither laugh nor cry.
  • Either the clerk or the secretary has the keys to the Rover.
  • (Using has is correct. Using have would be wrong.)
Read more about using a singular or plural verb with Either/Or and Neither/Nor.
  • The clerk or the secretary has the keys to the Rover.
  • (You can often omit the word either.)
  • He did not find the key either on or under the mat.
  • Neither the forwards nor the scrumhalf, all of whom were within 10 metres of the tackle, nor the crowd appealed for a foul.
  • (It is quite harsh to mark this as wrong, but grouping three things is an unpopular style that is likely to irk your readers.)

Beware Double Negative

The pairing neither/nor plays a negative role in the sentence. Be careful not to use a double negative.
  • Adam did not find the key neither on nor under the mat.
  • (This is a double negative.)
  • He did not mention neither the flooding nor the landslide.
  • (This is a double negative.)
  • He mentioned neither the flooding nor the landslide.
  • He did not mention either the flooding or the landslide.

A Double Negative Is Not Always a Mistake

Remember, a double negative is not always a mistake, but it might change the intended meaning. For example:
  • I haven't got no money.
  • (This is a double negative. It means I have money, which is almost certainly not the message the speaker wanted to convey.)
  • She is not unattractive.
  • (This is also a double negative. It could mean She is attractive or She is not ugly. In this case, the positive sentiment is probably what the speaker wanted to convey.)

See Also

What are conjunctions? What are double negatives? Either/or plural or singular verb?