the best/greatest thing since sliced breadinformal used humorously to say that something new is very helpful, useful etc 非常有用的新东西〔幽默用法〕 He reckons his new mobile phone is the best thing since sliced bread. 他认为他的新手机是最好的。
the best/greatest thing since sliced bread• Now, I didn't get it because I was the greatest thing since sliced bread.
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