There is only one ecosystem in Europe.

欧洲只有一个生态系统。

There is only one way to get the best of an argument—and that is to avoid it.

只有一种方法可以在争论中胜出——那就是避免争论。

There is only one sure way to succeed.

只有一种办法可以确保成功。

There is only one telephone in the office.

办公室仅有一部电话。

When two thirds are taken away, there is only one third left.

三停儿去了两停儿，还剩一停儿。

There is only one opening, but dozens of people are competing for the position.

只有一个名额，却有几十人抢这饭碗。

There is only one little problem.

只有一个小问题。

There is only one other person who could help us.

只有一个人能帮助我们。

There is only one rule.

这只是其中一条规则。

There is only one Harvard.

世界只有一个哈佛大学！