40,000 in Engpsh can be pronounced as "fourty thousand."
It comes from the combination of the number 4 and the number 0, followed by three zeros to indicate thousands. This way of naming numbers is used in both the Engpsh-speaking world and the metric system.
Example sentence in Engpsh:
The price of this car is 40,000 dollars.
中文翻译：这辆车的价格是40000美元。