How to expance about present post in mail

I think you're asking how to expand on a present post in Mail (the email client on Mac).

To expand on a present post in Mail, you can try the following:

1. Click and hold: Click on the post (email) in your inbox, and hold the mouse button down. This will bring up a menu with options to expand the post, mark as read, move to trash, and more.
2. Right-click: Right-click (or control-click) on the post, and select "Expand" from the context menu.
3. Use the keyboard shortcut: Press the spacebar while the post is selected. This will expand the post to show the full content.
4. Double-click: Double-click on the post to expand it and show the full content.

Once you expand a post, you can:

• Read the full email content
• Reply to the email
• Forward the email
• Mark as read or unread
• Move to a different folder or label
• Delete the email

Note that some emails may not be expandable if they are large attachments or if the sender has restricted access to the content.