渡江使用的船有一万只左右，所以我百万大军能够渡过长江。

We had about ten thousand boats on hand, enabling our one million soldiers to cross the river.

现在估测数量在两万到两万五的赔率最低，是6/4，然而数量在一万只以下的赔率高达20/1。

Bets around the current estimated population of 20,000-25,000 attract the shortest odds, 6/4, while pessimists opting for under 10,000 bears can get 20/1.

在北美这种动物现存一万只左右，他们全部都是由半个世纪以前的一个的物种进化而成，当时这个物种的数量只有三十只。

There are about 10, 000 of these animals in North America. All of them are descended from an original population of just 30 that was introduced half a century ago.