How to indent inward a block of text by a TAB or 4 spaces, in Emacs, in markdown-mode?

How to indent inward a block of text by a TAB 开发者_StackOverflow中文版or 4 spaces, in Emacs, in markdown-mode?

I mean manually triggering that for selected text.

In general, C-u C-x C-i will indent the marked block by 4 spaces (C-x C-i => indent-rigidly, C-u without following digits or minus sign => the implicit universal argument of 4). (First mark one end of the block with C-SPC and then move to the other end of the block, in case "marked" isn't a familiar concept.)

Judging from http://jblevins.org/projects/markdown-mode/, if you want to indent the block that way to mark it as code, you want C-c C-s c (after marking the block as above).