Simple Sentences:
* The choir sung beautifully.
* She sung a lullaby to her baby.
* The birds sung their morning song.
More Complex Sentences:
* The song was sung with such passion that it brought tears to my eyes.
* He sung a song he had written himself, which impressed the audience.
* The national anthem was sung by the entire stadium.
* She had sung in the shower for years before she finally decided to audition for the talent show.
Note: The word "sung" is the past participle of the verb "sing." It can be used in both passive and active voice sentences.