The past participle of the irregular verb ring, meaning “cause a bell or phone to make a sound,” is rung. The past participle is used to form perfect tenses and the passive voice (e.g., “The church bells had rung for hours in celebration;” “The doorbell had been rung”).
Sometimes you will see “rang” used as a past participle, but this is incorrect. It is the simple past tense of “ring.”
When ring means “encircle something” then the simple past and past participle are ringed (e.g., “The baseball ground was ringed with bleachers”).
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