weighted 4 bit code

例句：

1. 1. The heavy bag is too heavy for me to lift.
   这个沉重的袋子对我来说太重了，我举不起来。
2. 2. He weighed the book down with a heavy bookcase.
   他用一个沉重的书柜压住了这本书。
3. 3.The weighted ball is designed to help children develop their fine motor skills.
   这个带重物的球是为了帮助儿童发展他们的精细运动技能。