wagonmaster2 - there are 2 ways to do this.
If you want to quote the complete thread then you would click what looks like a "yellow manila folder with blue quotation marks" at the bottom right side of the post you want to quote.
The other way is to "copy" the part you want to quote and then you would click the seventh button from the left that is above your posting window that looks like "..."
and place what you want to quote in that box.. then click the "OK" button.
I hope this helps you.