| 1. | The world population goes up by two percent a year .
世界人口每年增加2。 |
| 2. | There were many ups and downs in the earth's numbers .
世界人口数量变化起伏不定。 |
| 3. | The approximate annual rate of world population is 2 percent .
世界人口每年的增长率约为2。 |
| 4. | The world's population has doubled during the last four decades .
过去40年中世界人口增加了一倍。 |
| 5. | World population today is very youthful, particularly in the third world .
今天，世界人口非常年轻，特别是在第三世界。 |
| 6. | We see that before 1650 it took nearly 35, 000 years, or about 1, 400 generations, for the world population to double .
我们可以看到，在1650年以前，世界人口的倍增，要经历将近35万年或近1400代人的时间。 |
| 7. | China is the world 's most populous country with a population of 1.1 billion , which makes up approximately a quarter of the world population .
中国是世界人口最多的国家，有11亿，约占世界总人口的四分之一。 |
| 8. | The world ' s population is growing faster and faster
世界人口的增长在越来越快。 |
| 9. | The problem is the world population is growing fast
问题是世界人口正在快速增长 |
| 10. | The problem is the world population is growing fast
问题是世界人口正在快速增长。 |
