2016天猫双十一全球狂欢节总交易额超1207亿元，再创世界纪录，但狂欢过后，很多人出现图中现象，这启示我们要（    ）

B

    Scientists say life will be very different in 2050.

    First, there will be no TV channels (频道) in 2050. People will choose a program (节目) from a computer and watch it on TV. In 2050, we will get information from the computers only.

    Second, water will be a big problem in 2050. In many places, people won't have water to drink.

    Third, cars will use new and clean fuels (燃料) and they will go very fast. There will be a computer in every car. And the computers will control the cars and there won't be any accidents (事故).

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