Early in the 20th century, the great mathematician David Hilbertnoticed that a number ofimportant mathematical arguments werestrcturally similar, In fact, he realized that at an appropriate level ofge...
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When meeting new people at a party, it is customary, out of politeness, to ask what one does. When it happens, I usually mumble that I am a doctor, but not the real kind, just the academic kind. Then,...
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共60讲!包含初一所有英语知识!
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