1. In 1871, American inventor Ives McGaffey realized that if you turned an air pump (气泵) the opposite way, you would have a machine that could pick up dirt.
    1871年，美国发明家艾夫斯·麦加菲意识到,如果将气泵的转动反个向,它就会变成一台能吸起灰尘的机器。

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