沒有可行性, 沒有可以控製的條件, 就沒有科學的實驗.

來源: gulala 於 2013-08-11 12:06:44 [舊帖] [給我悄悄話] 本文已被閱讀：次

每年的氣候不一樣, 如何可以做實驗

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