Correct 永冻层 / yǒng dòng céng / Strokes Example As a Noun permafrost 1 Yǒng dòng 永冻 céng 层 xiāo tuì 消退 Copy Pinyin Sentence degradation 2 Yǒng dòng 永冻 céng 层 róng jiě 融解 Copy Pinyin Sentence depergelation
