The population is increasing at about 6% per year.

　　人口以每年約6%的速度增加。

　　The disease affects fully 30 per cent of the population.

　　這種病感染了足足30%的人口。

　　The population has increased from 1.2 million to 1.8 million.

　　人口已從120萬增加到了180萬。