contraction of "do not"

"नहीं करना"

English Usage: I don't want to go.

Hindi Usage: मैं नहीं जाना चाहता।

to perform an action

"कार्य करना"

English Usage: I do my homework every day.

Hindi Usage: मैं हर दिन अपना होमवर्क करता हूँ।

a performance or action

"कार्य"

English Usage: It was a great do!

Hindi Usage: यह एक शानदार कार्यक्रम था!