1.
A rain cloud, especially a low dark layer of clouds such as a nimbostratus.
雨云雨云，尤指象雨层云一样的深色低云层
2.
A low, gray, often dark cloud that precipitates rain, snow, or sleet.
雨层云一种呈深灰色的低云层，预示有雨、雪或冻雨
3.
minimum penetration altitude
向下穿云的最低高度
4.
The sky was grey and the clouds were heavy and low.
天空阴沉，乌云低矮。
5.
The altitude of the lowest layer of clouds.
云幕高度最低层云的海拔高度
6.
There was heavy cloud and a lowering cloud base.
阴云密布，而且云层愈来愈低。
7.
Rain clouds hanging low over the corn fields.
雨云低低地悬浮于玉米地的上空
8.
He navigated the plane through the low cloud.
他驾驶飞机穿过低低的云层。
9.
Low-level jet and monsoon cloud swell are the most important factors for thedevelopment of cloud clusters.
低空急流和季风云涌是云团发展的最重要因子。
10.
A grey miasma, neither cloud nor mist, hung low in the sky and the atmosphere was stifling.
一些似云非云，似雾非雾的灰气低低的浮在空中，使人觉得憋气。
11.
The rain ceased but the clouds hung low and heavy overhead.
雨停了，但是阴云密布，低低地笼罩在头上。
12.
The lowering clouds presage a storm.
暗云低沉是暴风雨的前兆。
13.
lowering storm-clouds covered the sky;
孕育着风暴的黑云低垂，布满天空；
14.
Black storm clouds were low and heavy over the Gulf.
黑压压的积雨云低垂在墨西哥湾上空。
15.
The ceiling was so low that the patrol was flown contact.
云层很低，巡逻机只好进行目视飞行。
16.
Dark Clouds hung overhead, and a heavy snow fell.
乌云低沉沉的，天下着大雪。
17.
Determination of the minimum ignition temperature of dust cloud
GB/T16429-1996粉尘云最低着火温度测定方法
18.
The sun was low and soon it would be behind the clouds.
太阳低垂，一会就要没入云层背后去了。