How to politely ask someone to complete a task

1. How do you professionally ask someone to complete a task?
2. How do you politely ask someone to check something?

How do you professionally ask someone to complete a task?

Explain the reason for the request. Give a deadline when possible. Give dates clearly. Make your request polite by starting it with Do you think you could … ? or I would be grateful if you/we/I could … .

How do you politely ask someone to check something?

Try one of these: I would like to kindly ask you to check ... Would you be so kind as to check ...