“层积”用英语怎么说

实践上, 种子不需要干藏而是采种后即层积.In practice, seeds should not be stored dry but stratified on removal from the fruit.我爬上三层积满灰尘的楼梯, 禁不住凄然泪下,又加衣衫单薄冷得直打哆嗦.I went up three dusty flights of stairs and I cried, shivering in my thin coat....

“层积”的拼音为：céng jī...