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數學不是一項觀賞性運動。

The streets of Paris have a memory of their own.

記憶是個奇怪的東西，它不像相機或錄音機那樣工作，它會重建事物，用現在的剪刀剪輯過去。

Positive emotions are not trivial luxuries, but instead may be critical necessities for optimal functioning.

The industry must collaborate to reduce its environmental footprint.