若F是R中一紧集(即有界闭集)且F不等于R,则F是从一闭区间中挖去可数个互不相交的开区间后所得之集。()
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These problems defy easy classification.英译汉
It would be astonishing if that loss were not keenly felt.英译汉
The Success of thiscal"shows the importance of good design in helping to sell the product.
I was so impressed by these words that I used them later for a Christmas card.英译汉