by all means
A polite way to say 'yes, of course, please do'.
Want to use my umbrella? By all means, take it.
By all means is a polite way to give permission: 'Yes, of course, go ahead.' Use it when someone asks to do something.
Your turn
Complete it: 'May I open the window?' – '___, go ahead!'
Complete it: 'May I open the window?' – '___, go ahead!'