The 'burden of proof' is on the plaintiff, since the defendant is presumed innocent until proven guilty. [=the plaintiff must prove that the defendant is guilty]
The 'tax burden' has been falling increasingly on the middle class. [=middle class people have been paying a greater portion of taxes]
For the rest of his life he 'was burdened' with the knowledge that he had done nothing to help them.
(..) with ghosts? and I realized that one of Richard's problems is that he's got no family here. He's got no support system. So the burden of helping him has kind of fallen on me. Okay, fine. Hey, maybe since you have all those ghosts there, you can get one to help us out when you're done. (..)2004 TvShow: Charmed Title: I Dream of Phoebe Season: 6 Episode 15