A frog can't empty its stomach by vomitting. To empty its stomach contents, a frog throws up it's stomach first, so the stomach is dangling out of it's mouth. Then the frog uses its forearms to dig out all of the stomach's contents and then swallows the stomach back down again.
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Jingle Bells.. Batman smells.. Robin layed an egg.. the Batmobile, lost its wheel.. and the Joker got away.. :D