5 The world's different sorts of natural resources are
struggling to support a 1 and it may result in a long
term crisis.
6 To feed 2 billion more mouths predicted by 2050, food
production will have to 2.
  • 1、
  • 2、
【正确答案】 1、rapidly growing population,    2、increase by 70%    
【答案解析】 题干中的have to后接动词原形，increase后面常接by。