填空题
The world’s population continues to grow. Now there are about (11) （）of us on earth. That could reach 6 billion by the end of the century and (12)（）in further 75 years. Experts have long been concerned about such a growth. Where will we find the food, water, jobs, houses, schools and health care for all these people
A major new study shows that the situation (13) （）. A large and rapid drop in the world’s birth rate has taken place during the past 10 years. Families generally are smaller now than they were a few years ago. It is happening in both (14) （） nations.
China is one of the nations that have made great progress in reducing its population growth. China has already cut its rate of population growth by (15)（）since 1970.