1 . I think __________ you will like him. （用适当的词填空）

2 . One day, my five year old son asked me ______ there was ham in a hamburger. (用适当的词填空)

3 . Sometimes, I really doubt ______ there is hope in my Math. （用适当的词填空）

4 . He is constantly thinking of ______ he could do for others. （用适当的词填空）

5 . The policy has allowed China to accomplish in just four decades________took Western industrialized countries more than 200 years to achieve.（用适当的词填空）

6 . Desertification, the name for ____________ happens when land that can be used to grow crops turns into desert, is a growing world problem.