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淡水在上層向下流動(dòng),比重更大的鹽水在下層逆流向上.The salt water, being more dense, flows upstream under the fresh water which is flowing downstream.海上風(fēng)浪大作,我們都躲在下層甲板.The sea was rough and we were all below.大部分的問題發(fā)生在下層.Most problems have occurred...