Since I realize that English is a difficult language, I looked this up in Merriam Webster for everyone to reference:
sing
intransitive verb- to produce musical tones by means of the voice
- to utter words in musical tones and with musical inflections and modulations
- to deliver songs as a trained or professional singer
- to make a shrill whining or whistling sound
(just for the record, I looked this up for a native English speaker) ;-)