RhymeZone: could definitions

Definitions of could:

verb: simple past tense of can
verb: Used as a past subjunctive (contrary to fact).
verb: Used to politely ask for permission to do something.
verb: Used to politely ask for someone else to do something.
verb: Used to show the possibility that something might happen.
verb: Used to suggest something.
noun: Something that could happen, or could be the case, under different circumstances; a potentiality.

(Definitions from Wiktionary)

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