Level: intermediate

A few plural nouns refer to things that have two parts. They have no singular form. These are always things we wear:

glasses/spectacles trousers shorts
pyjamas pants boxers
tights jeans knickers

Those trousers are too long.

or implements:

pliers scissors binoculars pincers

These binoculars were very expensive.

To make it clear we are talking about one of these items, we use a pair of …:

I need a new pair of spectacles.
I've bought a pair of blue jeans.

If we want to talk about more than one, we use pairs of …:

We've got three pairs of scissors, but they are all blunt.
I always carry two pairs of binoculars.

Singular, plural or both?

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