红色的天空是好天气的征兆，而乌云则是下雨的征兆。

Red sky is a sign of good weather, but black clouds are a sign of rain.

youdao

红色的天空是好天气的征兆，而乌云则是下雨的征兆。

Red sky is a sign of good weather, but black clouds are a sign of rain.

youdao