Yes, thanks. How's Kate?

很好，谢谢。凯特好吗？

He was just falling asleep when there was a loud knock at the door.

他刚要入睡，就有人很响地敲门。

How much did you pay for all these things? asked her mother.

“买所有这些东西你付了多少钱？”她妈妈问。

Uncle Wang, may I ask you some questions, please?

王大叔，我可以问你一些问题吗？

I know that he's doing his best, but he says that he is a little weak in Chinese.

我知道他非常努力，但他说他的中文有点儿差。

What was the population of the world in 1950?

1950年世界人口是多少？