mass of:
π-meson π介子的质量Examples:1. I found a mass of spawn in the fish before cooking. 烧鱼前，我发现鱼里有很多鱼籽。2. A cloud is a mass of vapor in the sky. 云是天空中的水汽团。3. A cloud is a mass of vapour in the sky. 云是天空中的水汽团。4. A great mass of rock had fallen from the cliff and now blocked the road. 一大堆岩石从悬崖上掉了下来，
a mass of 一大堆，一大团，里面的数不可数 - a mass of mud, 一堆泥土 amount of 不可数 number of 可数what's the amount of sand ...? 多少沙what's the number of students .. ? 多少个学生many of 大多数 - 可数，most
