We can't see underlining here, but here, I think this will be helpful:
"I read a novel" would be the intependent clause: it does not need the other one to be complete.
"until the guests arrived" is the subordinate clause: it needs the independent, main clause to be complete.
The support the sentence offers to a proposed solution is the following one:
Peer testimonial.
It is said that Lisa, a friend (a peer), uses a certain device which helps her manage her finances when it comes to paying heating bills. Therefore, a solution is proposed by offering a peer testimonial, that is, something a friend does which probably works for him or her and can work for someone else as well.
Lane used a text to world connection! pollution in the great barrier reef is a real world issue that he was able to compare to the text. hope this helps:)
