Question

what is subject? why is it called so?​

Answer 1

Answer:

Traditionally the subject is the word or phrase which controls the verb in the clause, that is to say with which the verb agrees (John is but John and Mary are).

Answer 2

The subject of a sentence is one of the basic parts of a sentence. The other basic part is the predicate. The predicate tells us something about the subject (i.e., it tells us what action the subject is performing, or it describes the subject

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