估计问题的性质不同。在这里，我们不关心检验特定的假设，而是关心估计参数的值。

It's difficult to extract sense from strings, but they're the only communication coin we can count on.

In the actual world， a very great deal of the evil that is done does not spring from evil motives.

The future of energy is low carbon, and we need to be at the forefront of that transition.