Nevertheless, our problems are aggravated by rapid growth in the human population, which is projected to reach eight or even nine billion by 2050. If the increase continues beyond 2050, one cannot help but be gloomy about most people’s prospects.
然而，人类人口（预计到2050年将达到80亿，甚至90亿）的迅速增长加重了我们的问题。如果人口在2050年之后继续增长，大多数人将前途堪忧。