Using course tools>>Discussion Board>>Participating in forums
To respond to a message in a Discussion Board forum:
If necessary, click the title of a thread in the forum to see a list of all the messages associated with the thread.
Click the title of the message to which you want to respond.
Click Reply.
Type your response in the Message box and select one of the options for displaying the text:
Smart Text displays the text as you enter it but converts URLs and e-mail addresses into links.
Plain Text displays the text exactly as you enter it, with no links.
HTML displays the text as you format it using HTML tags.
If you want to hide your identity and the option appears, select Post message as Anonymous.
(Optional) Attach a file.
Click Submit.