卷云是“一种低矮的长管形云彩，”它时而平滑，时而臃肿。

A roll cloud is "a long, low tube of a cloud," sometimes smooth, sometimes bumpy.

youdao

卷云是“一种低矮的长管形云彩，”它时而平滑，时而臃肿。

A roll cloud is "a long, low tube of a cloud," sometimes smooth, sometimes bumpy.

youdao