What happens if you see twin witches?
You won't be able to tell which witch is witch

What did the skeleton say when his brother told a lie?
You can't fool me, I can see right through you

Will: 'Mum, all the children make fun of me.'
Mum: 'What do they say?'
Will: 'They say I'm a werewolf. Is it true?'
Mum: 'Of course not. Now comb your face and get ready for supper.'

These and many more howlers to make you laugh your head off (in most cases not literally).