Unit5 Water第一部分 词汇drop 滴;掉下,落下I’m a drop of water. Be careful not to drop that plate. (两句话中drop的区别)journey 旅行,旅程Is this the end of your ? 这是你旅程的终点吗?quantity. 数量I only bought a small quantity of cheese.【in large quantity】大量地It is cheaper to buy things in large .4. experiment 5. fresh 淡的,无盐的About 3% of the water on Earth is “ fresh&rdq..