Eustasy
海面进退; 海面升降; 冰河变异
🗣️ 情景例句
If the owners don't claim the dog in forty-eight hours,
如果狗的主人在四十八小时内不认领，
I don't know for sure.
我不能肯定。
Experiments have proved that children can be instructed in swimming at a very early age.
实验证明，儿童在很小的时候就可以开始学习游泳。