we better change the definition accordingly.

我们最好把定义也改一下
We'll come back and talk about what it means in a second a bit more,

我们等会还会回头更详细的解说其意义
but first we better make sure we have an okay definition for it.

但首先我们必须要给它一个合适的定义
So what I'm going to do is I'm going to drag this definition down

我下面要做的就是下个定义
and do something you're not meant to do usually in teaching,

还要做些一般上课不经常做的事
I'm going to use the eraser to correct my definition.

我要用黑板擦来修正我的定义
So here I have my pure strategy definition

这里有我的纯策略的定义
and let me just change it into a definition

让我来把这个定义改一下
that will allow for these polymorphic populations.

以便适用于多态的情况
So I'm going to change this into a P,

所以我要把这个改成P
I'm going to change this pure into mixed,

我要把这些纯策略改成混合策略
and everywhere you see an ?

把下面的?