Introductory Requests & Commands

Use a Writing.lifetips.com/cat/56416/commas/index.html">comma after an introductory request or command.

Look, we´ve discussed this before.
You see, I haven´t finished my report.
Please remember, Christmas will be here soon.

Exception: "Please remember that ..."
When "that" is added, "please remember" becomes the main verb and is no longer an introductory element.