(auxiliary) A syntactic marker.

To perform; to execute.

“All you ever do is surf the Internet. What will you do this afternoon?”

To cause, make (someone) (do something).

(of food) Ready, fully cooked.

“As soon as the potatoes are done we can sit down and eat.”

Having completed or finished an activity.

“He pushed his empty plate away, sighed and pronounced "I am done."”

Being exhausted or fully spent.

“When the water is done we will only be able to go on for a few days.”