tiān / shàng / wū / yā / yā / de / yún / céng / yù / zhí / zhe / mǎ / shàng / jiù / yào / xià / dà / yǔ / le

天上乌压压的云层预示着马上就要下大雨了。

The dense clouds in the sky indicate that a heavy rain is coming soon.