—Determiners are one of the eight main word classes. 

—You will always find a determiner before a noun (unless an adjective sneaks in first!) 

For example: 

The children went outside. 

Children is a noun - it is the name of a group of young people. 

The is a determiner - it introduces the noun. 

—There are five main types of determiner. All introduce nouns but each has a slightly different role:

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