The scientists said the area they researched formed the atmosphere in the lower clouds.

科学家们表示，他们研究的这片区域在较低云层中形成了大气层。

The scientists analysed the structure of airborne microbes in the lower clouds over the Southern Ocean.

科学家们分析了南大洋上空较低云层中空气微生物的结构。

His eye, alone, which glistened like a fiery star amid lowering clouds, was to be seen in its state of native wildness.

只有他的眼睛，在低垂的云层中像一颗炽热的星星一样闪闪发光，让人看到它原始的野性状态。

One morning, though, I awoke and saw the whole of B. overborne by dark, lowering clouds racing across the sky. I knew exactly what this spelled. Autumn was just around the corner.

有一天早上，我醒来，看到黑暗笼罩Ｂ城，阴沉沉的乌云快速飘过天际。我完全清楚这意味什么。秋天不远了。

The autumn leaves were falling during the last few days which I passed in the valley, days of lowering clouds, which do sometimes obscure the heaven of Touraine, so pure, so warm at that fine season.

在我经过山谷的最后几天，秋天的树叶正在飘落，云层在降低，有时会遮蔽都兰的天空，在那个美好的季节，它是如此纯净、如此温暖。