Some nouns are always plural. For example:
- Scissors
(scissor) - clothes
- glasses
- contents
- trousers
- police
Look at these examples:
- Please can I borrow your scissors.
- Your clothes are all over the floor.
- I want to read the newspaper, but I can’t find my glasses.
- The contents page is always at the beginning of a book.
- I need to buy a new pair of trousers.
- The police are investigating it.