The trouble is, she really does. Matilda, roller-skating past friends Elmer (Elephant), Alex (Alligator), Mollie (Octopus), Leo (Lion), etc., insults each of them in turn; then, she slips on a wet spot, falls on her face, and berates them for not warning her! Looking daggers, they hustle off--and the next thing Matilda sees, painted on a fence, is: ""MATILDA HIPPO HAS A BIG MOUTH."" She opens her big mouth and bawls, apologies are exchanged, Matilda changes the ""HAS"" on the sign to ""HAD,"" and everybody's happy. Except, maybe, the three-year-old (it's a very simple, very young book) who has never heard the expression, ""to have a big mouth""--and can see perfectly welt that Matilda Hippo's mouth is as big as ever. Up to that point--with its fiat, bright, clear-cut pictures and comical visages--it's pretty funny.