苯异海因

This is Scientific Americans 60-Second Science. Im Steve Mirsky. Got a minute? To keep your car purring, you have to change the oil. Such maintenance produces eight billion gallons of used motor oil annually. Some waste oil does get re-refined to pro

发表于:2018-12-24 / 阅读(72) / 评论(0) 分类 Scientific American(三)月

A: I am kind of confused about the in-flight instructions and need to ask you a few questions. B: It would be my pleasure to help you with any questions you might have. A: Where is that card that shows my nearest exit? B: That card is in the seat poc

发表于:2018-12-30 / 阅读(40) / 评论(0) 分类 旅游英语对话

A: Would it be all right if I asked you a few questions about your in-flight instructions? B: I would love to help clarify any questions you might have. A: When you were talking about the nearest exit, what were you talking about? B: Theres a card in

发表于:2018-12-30 / 阅读(34) / 评论(0) 分类 旅游英语对话

A: Can I ask you some questions about the in-flight instructions? B: I would be happy to help you clarify anything you need help with. A: Could you help me find out where my nearest exit is? B: There is a card in your seat pocket that shows you where

发表于:2018-12-30 / 阅读(42) / 评论(0) 分类 旅游英语对话

This is Scientific American's 60-Second Science. I am Steve Mirsky.Got a minute? Talk about your vicious cycles. A new study finds that belly fat could be making you hungrier. Which would lead to more belly fat. The research was performed at the Univ

发表于:2019-01-08 / 阅读(73) / 评论(0) 分类 Scientific American(四)月

Algae seem harmless enough. These precursors to plants thrive throughout the world's waters. But these single-celled plants have global consequences. We can thank them for oxygen in the atmosphere, oil in the lithosphere as well as dead zones in the

发表于:2019-01-08 / 阅读(56) / 评论(0) 分类 Scientific American(十一)月