Audio problem: When Jacob and Bella are in the car, on the way to Charlie's, Jacob is laughing about "Dracula 1 and Dracula 2" being "creepy." He lets out a huge loud, chuckle in the audio, yet the audio doesn't match his mouth, as his mouth is merely in a tight grin.
The Twilight Saga: Breaking Dawn - Part 2 (2012)
1 audio problem
Directed by: Bill Condon
Starring: Kristen Stewart, Robert Pattinson, Maggie Grace, Taylor Lautner, Peter Facinelli
Continuity mistake: At the end, when Bella is thrown into Edward, she is wearing shoes with a heel, but a few seconds later she is wearing regular boots. (01:32:50)
Bella Swan: You nicknamed my daughter after the Loch Ness Monster?
Question: Can vampires and werewolves be killed or injured by anything other than vampires and werewolves?
Answer: Sure. The problem is that these films portray vampires and werewolves as having super-human abilities, so it'd be significantly harder for a regular person to kill one. But nothing about the films seems to indicate it's overtly impossible.
Answer: Aro also makes the argument that for the first time in our history humans pose a threat to our kind with their weapons that can destroy us. Theoretically any weapons that can tear apart and/or burn the vampires would work. So, yes, things other than vampires and werewolves can kill the vampires and werewolves.