Multi Quotes
You push that button on multiple responses if you wish to quote those responses - and they are placed in your response - so you can respond to what multiple people had commented on.
So, if multiple people said things you wish to quote, just click on those little buttons to include each of them, and once you've chosen everyone, then hit 'reply' and all those quotes will show up in your response - and you can key in comments around them (just be careful not to erase or change any of the brackets around the quotations, as that is code for the system to parse when looking at what you've written).
//sse