Once the soil has been removed by erosion, only the passage of centuries or millennia will enable new soil to form.
一旦土壤被侵蚀，新的土壤只有经过几个世纪或几千年才能形成。
2
Not only do melting snow and ice flow directly into the sea, they also form torrential under-ice streams that lubricate the passage of glaciers toward the ocean.
融化的冰雪不仅直接流入大海，还在冰下形成湍流，为冰川滑向海洋大开方便之门。
3
Choose the correct order of the following sentences to form a passage.