translation.en: You know how much trouble the children have with variables, but by learning it this way, in a situated fashion, they never forget from this single trial what a variable is and how to use it.
translation.zh: 孩子们对于变量这个概念很难把握 而假如他们是在类似的情景下去学习 他们永远也不会忘记自己所做的实验 不会忘记何为变量 也不会忘记变量的使用方法