To add multiple quotes to a post all you need to do is copy and paste the text you'd like to quote and then surround that with quote tags.
For example:
CODE
[quote]This is a quote[/quote]
Comment on the quote
[quote]This is another quote[/quote]
Another comment
Would produce the following :
QUOTE
This is a quote
Comment on the quote
QUOTE
This is another quote
Another comment
You can also add a name to the quote to show who you are quoting.
CODE
[quote name='SaRuMaN']This is a quote[/quote]
Would produce:
QUOTE (SaRuMaN)
This is a quote