敏感栅越窄，基长越长，横向效应越大。
A. 对
B. 错
According to the video, how much of the world’s food is wasted each year?
A. a half
B. a third
C. a quarter
What are "leftovers"?
A. remains of food or a meal, which have not been eaten
B. a thing that is completely without value
C. lost stuff
What is the other way to say "dump"?
A. leftover
B. landfill
C. a waste of space
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