Fatima, let me explain it to you. I know that text is long, but read it, you will learn a lot from it.
We have countable and uncountable nouns in the grammar. I am sure that you can differenciate count nouns such as apple, banana, ball, glass etc. from non-count nouns such as sugar, coffee, flour, milk and so on. You must keep in mind that nouns such as information, news, music, progress, luggage, business, furniture, advice, knowledge don’t have plural, therefore here is your answer that you have been looking for. You always use them in singular. What time is news on television? The same thing with information, you cannot say I gave you a information, but you can say I gave you some information.
Ok, now when you know the difference, let me add something more in order to teach not only you, but everyone who reads this text.
Nouns that have irregular plural are: Foot-feet, man-men, woman, women, child-children, mouse-mice, tooth-teeth, goose-geese and so forth.
The following nouns have the same form in singular and plural: Sheep-sheep, means-means, species-species, deer-deer, fish-fish, series-series, and so on.
Compound nouns form their plural by adding S to the principal word: Sister-in-law-sisters-in-law, writing-table, writing-tables etc.
Sometimes we use a plural noun for one thing that has two parts. For example: Trousers, pyjamas, glasses, binoculars, scissors. Those are nice jeans, or that is a nice pair of jeans.
I’m glad I had an opportunity to explain this to you, so read and learn, it’s not as difficult as it seems to be. Take care :)