(CNN) In a speech in Iowa on Tuesday night, Republican presidential frontrunner Donald Trump -- who has regularly promoted his negotiating skills as a selling point for his presidency -- used broken English to briefly impersonate Asian negotiators.

"When these people walk into the room, they don't say, 'Oh hello, how's the weather? It's so beautiful outside. How are the Yankees doing? They're doing wonderful, that's great," Trump said, to some laughter from the crowd. "They say, 'We want deal!'"

Trump said Jeb Bush, the former Florida governor and his chief Republican primary opponent, is "low energy" and would "jump out of the seat" at such a declaration. In many polls, Bush is polling second nationally behind Trump and is the most frequent target of Trump's ire.

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