A:Great!Can you tell me something about the book? B:Certainly!It says 1000 years ago,the world's population was small, (2)
A:Really? B:Yes,but during the last three or four hundred years,the world's population has grown very quickly.Today,it is growing faster than ever before. (3)
A:Sorry,I don't know. B:It's more than 7 billion. A:It's so large.(4)
B:Yes,if we don't control(控制)the population,there will not be enough space even to stand in on the earth in 600 years. A: (5)
A.Do you know what the world's population today is? B.I'm reading a book about the world's population. C.I think we must do something to control the population. D.It's too terrible. E.It's less than 1 billion.