A change in the form of a word to reflect different grammatical functions of the word in a sentence. English has lost most of its inflections. Those that remain are chiefly possessive ('s), as in “the boy's hat”; plural (-s), as in “the three girls”; and past tense (-d or -ed), as in cared. Other inflections are found in pronouns — as in he, him, his — and in irregular words such as think/thought, child/children, and mouse/mice.
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