Uncountable or mass nouns refer to materials, liquids, abstract qualities, and collections that cannot be counted individually. Examples include wheat, sand, weather, and water. Uncountable nouns are singular and do not take plural forms or numbers. Some nouns like travel can be either countable or uncountable depending on whether they refer to a specific instance or the concept in general. Additionally, some nouns like scissors are always plural even though they refer to a single object.

1. UNCOUNTABLE NOUNS
Uncountable or mass nouns are the names of materials, liquids, abstract qualities,
collections and other things which we do not see as separate objects. Most
uncountable nouns are singular with no plurals. Examples are: wheat, sand, weather,
water, wool, milk
We cannot use numbers with uncountable nouns. They are also not normally used
with the article a/an.
 accommodation (a place to live)
advice (a piece of advice)
baggage (a piece of baggage; a bag, a case)
behaviour (a piece of behaviour)
 bread (a piece of bread; a loaf; a roll)
chess (a game of chess)
chewing gum (a piece of chewing gum)
equipment (a piece of equipment; a tool)
furniture (a piece/article of furniture)
grass (a blade of grass)
 homework (a piece of homework)
information (a piece of information)
knowledge (a fact)
lightning (a flash of lightning)
luck (a bit/stroke of luck)
luggage (a piece of luggage; a bag)
 machinery (a piece of machinery)
money (a note; a coin; a sum)
news (a piece of news)
 permission
poetry (a poem)
 rubbish (a piece of rubbish)
 scenery (a piece of scenery)
thunder (a clap of thunder)
 traffic
travel (a journey/trip)
 weather
work (a job; a piece of work)

2. Countableor uncountable
Sometimes it is not easy to see whether a noun is countable or uncountable. For
instance, travel is normally uncountable, while journey is countable. It is impossible
to give complete details. The following rules, however, should help.
Illnesses
The names of illnesses are usually uncountable in English. Examples are:
chickenpox, measles, cancer, diabetes, flu etc.
 If you have had chickenpox, you can’t get it again.
But note that the words for some minor ailments are countable. Examples are: a cold,
a headache
 I have a bad headache. I’ve been having headaches.
Mixed uses
Many nouns have both countable and uncountable uses, sometimes with a difference
in meaning.
Words for materials are usually uncountable. But note that the same word is often
used as countable noun to refer to something made of the material.
 Have you got some typing paper? (uncountable)
 I want a paper. (countable)
 Have you got any coffee?
 Could I have two coffees? (= two cups of coffee)
Many abstract nouns are uncountable when used in a general sense. The same
noun can be countable in a particular sense.
 She hasn’t got enough experience for the job. (uncountable)
 It was a strange experience. (countable)
 Take your own time. (uncountable)
 Have a good time. (countable)
Plural uncountable nouns
Some uncountable nouns are plural. They have no singular forms with the same
meaning, and cannot be used with numbers. Examples are: trousers, jeans, pyjamas,
pants, scissors, spectacles, glasses, arms, goods, customs, groceries, clothes and
thanks
 Have you bought the groceries?
 Many thanks for your help.