So, fuel economy and environmental conservancy make a lot of sense if you care about such things, of course.

所以，油价和环境保护,是很有意义的,如果你关心这样的事，当然会更好。

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In the meantime, I believe that the U.S. is doing quite a bit of work in terms of raising fuel efficiency standards,

同时，我相信美国在提高燃料效率标准方面做了不少事，

对全球变暖的政策 - SpeakingMax英语口语达人