America has a big problem, a populationreplacement process in progress.
美国有一个大问题，那就是正在发生的人口更替过程。
2
There are several reasons to be concerned about the below populationreplacement fertility levels in all of Europe and about half the world's population, including China and Japan.
在整个欧洲和几近半数的世界人口中，包括中国和日本，对于下降的人口更替生育水平有一些原因可以考虑。
3
In France the fertility rate is already around two children per female, not far short of the “replacement rate” which keeps population numbers steady.