Mac Keyboard Shortcuts: Selecting non-adjacent Messages In Mail

Hi,
On my Mac, I can hold down SHIFT while pressing DownArrow to move more than one message. I was wondering if the Mac has a key stroke to skip items I want to move. On PC, I can hold the CONTROL key and tap the SPACEBAR to select items to move in, for example, File Explorer. I was guessing that perhaps Mac has the same ability by using the Command key. I can't tell which items are selected in Mail, though, because my Mac reads the message window and does not say the word selected to tell me that rows in the Messages table are selected.