UNCOUNTABLE NOUNS

Some English nouns usually cannot form a plural or be preceded by a, an or a number. Because they usually cannot be preceded by a number, such nouns can be referred to as uncountable. English uncountable nouns include:

a) nouns naming intangible things which normally cannot be counted:
e.g. honesty
      courage
      impatience

b) nouns naming tangible things which are thought of as substances:
e.g. butter
      milk
      sand

c) nouns naming groups of things which in English are referred to collectively:
e.g. furniture
      luggage
      news

d) names of languages:
e.g. English
      German
      Spanish

An uncountable noun takes a singular verb.
e.g. Honesty is a virtue.
      Butter tastes good.
      Furniture was provided.

5 Exercises for uncountable nouns(with answers):

Exercises (1,2,3,4,5)

See also:

Singular countable nouns

Plural countable nouns

Uncountable nouns

Nouns indicating possession and compound subjects

Source: English Grammar