grammar

Is it right? who can help me?

The novel of that takes the love story of Baoyu and Daiyu as its main line ("main theme" would be better) tells us of the decline of four big families.

I'm guessing a bit Hel, but

The (A?) novel that takes (taking?) the love story of Baoyu and Daiyu as its main line (theme?) tell us (addresses? explains?) the decline of the Four Big Families

Edited to remark that S. above largely beat me to the punch