If the probability is zero that means the event can't happen.

如果概率等于0就意味着事件不会发生
If the probability is one, it means that it's certain to happen.

如果概率等于1就意味着一定会发生
If the probability is--Can everyone see this from over there?

如果概率是...大家都能看清黑板吗
I can probably move this or can't I?

不知道这黑板能不能移一下
Yes, I can. Now, can you now--

看来能移现在看得见了吗
you're the most disadvantaged person and you can see it, right?

你的位置最不好了但你也能看见吧
So that's the basic idea.

这是概率论中最基本的概念
One of the first principles of probability

概率论中最基本的一个原则
is the idea of independence.

就是独立性的概念
The idea is that probability measures

概率是用来描述
the likelihood of some outcome.

某一结果发生的可能性
Let's say the outcome of an experiment, like tossing a coin.

比方说某一试验的结果比如抛硬币