Note: The two-word expression all ready means “entirely ready” or “prepared.” The one-word expression already means “previously” or “so soon.” Though indistinguishable in speech, these expressions should appear properly spelled in writing.
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Example: He reached the platform of the car, though the train was already moving. adverb (meaning “previously” and modifying the verb was moving)
Example: She was all ready to leave on her vacation. adverb (modifying the verbal phrase to leave on her vacation)