3 Detailed Comprehension
Directions：Answer the following questions briefly according to the content of the video you have just watched.
1）What does the idiom“Don’t judge a book by its cover”mean in this video？
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2）What does“clone”mean in this video？(https://www.daowen.com)
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3）What does the proverb“Iron sharpens iron”mean in this video？
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