What is the key syntactic difference between a "Complement" and an "Adjunct" in a sentence structure?

Question

Accepted Answer

Complements are grammatically required to complete the verb's meaning, while adjuncts are optional additions.

Answer

Adjuncts are grammatically required by the verb, while complements are entirely optional.

Answer

Complements are highly mobile and can change positions, while adjuncts have a strictly fixed position.

Answer

Complements modify nouns, while adjuncts modify full verb phrases.

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