Click on the quote button at the bottom of the first post and select the entire post, copy, then hit the browser's back button and get out of that intent to reply, and then hit the quote button at the bottom of the second post and paste the first post's selected text, quote tags and all, (edited for germaneness), at the top of the reply window, thusly...

first post:
...Could you tell me how to post replies in which there are several quotes split up by text?


Then drop down below the quote-block and comment on that particular isolated quote.

And then move on to the second post's quote-block, which is already automatically in the window, because it is that post which is technically being replied to, --even though both messages are being replied in new post.

Then move down and edit out extraneous dialogue from the quote-block which you don't want to address in this particular reply.

second post:
...if there is a faster method, please tell us. My help is almost as bad as the blind leading the blind when it comes to computers.


And follow likewise with comments related specfically to that take on the point.

_________________
Ken