书城教材教辅科学读本(英文原版)(套装1-6册)
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第279章 第三册(104)

"No, that I certainly didn"t," said Fred. "It waseasy to think of the use we make of it for lighting and heating purposes. But when teacher said he was going to talk to us about balloons, I began to wonder what balloons had to do with coal-gas.""Why, of course," said Norah, "they can havenothing to do with it."