The doctors have told me that my days are numbered. [=I will die soon]医生告诉我说我的日子不多了。

He knew that his days as the team's coach were numbered. [=that he was going to be fired from his job as the team's coach soon]他知道自己当球队教练的日子屈指可数了。

The days of large gas-guzzling cars are numbered. [=people will not be making/buying large gas-guzzling cars for much longer]高油耗汽车就快要退出市场了。