How can I delete all emails at a time?

[Water Lin]

I know I can delete emails one by one by B Del.

I also know that I can delete emails at one time by mark them by # and
then use B Del.

But It is still a dirty way. I need to mark emails one by one.

Is there any way I can delete all emails in my mailbox without using
mark command # ?

or is there any way I can mark all emails at one time? like using # one
by one......

Thanks

Water Lin

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Email: WaterLin@ymail.com