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Grammar help: verb to be 'is/isn't, are/aren't'
Example:
The TV is powered by electricity. = 1 (singular)
Trees aren't powered by electricity. = 2+ (negative plural)
Description:
The word 'is' is used to talk about a person or thing (1 = singular).
The word 'are' is used to talk about people or things (2+ = plural).
'not' is used in the negative form and is usually shortened to n't (isn't/aren't).