how to delete multiple emails onetime on mac

if the emails are adjacent to each other, you can click on the top one of the list and then press and hold the "shift" key and click on the bottom one on the list. they will all become highlighted and you can then use the "delete" key to delete them.

if they are not adjacent, just press and hold the "command" key while clicking just the ones you want to remove. they will become highlighted. you can then use the "delete" key.

and finally, if you want to clear out an entire mailbox's mails, you can click on any one of the emails on the list, then use Apple Menu > Mail > Edit and choose "select all". then use the "delete" key.