not understanding sweeps

[harkeychad]

I have an attachment showing a covered porch on the back of the home. Someone gave me these rafters. it is not exactly what I want and I still can not figure out how he did it. I am not getting the whole sweep thing yet? Can someone explain a little bit on how to do this in lamens terms? Along with this, how do I cut the rafters that go through the walls? The last question is about joining roofs. I have attached roofs together from the 3d view but the underside of the roof still is shown. Basically I would like the two roofs to trim together. When I do a camera view of the interior, you can see the roof coming all the way down into the room. Like I said before, I need to attach,trim or something the two roofs so the underside trims as well.

Hope this is enough information to get some answers.

Thanks