11. Since people are always not satisfied with their present situation, they want further development.

　　改进: Since people are never satisfied with their status quo, they want further development.

　　12. The only thing they need to do is to find a job which can easily get big money.

　　改进: The only thing they need to do is to find a job that can bring them big money.

　　13. They like an active life but not a peaceful life.

　　改进: They like an active life rather than a peaceful one.

　　14. Some cigarettes may even cost a larger sum of money.

　　改进: Some cigarettes may cost even more.

　　15. Firstly, dissatisfaction encourages the discovery of new products.

　　改进: Firstly, dissatisfaction encourages the invention of new products.

　　16. Insgroupsto suit the needs of enteringsintoswork, students must grasp some technical skills.

　　改进: Insgroupsto meet the needs of future work, students must learn some practical skills.

　　17. It is very necessary more qualified scientists and technicians.

　　改进: Qualified scientists and technicians are in great demand.

　　18. This knowledge will become a part of your body.

　　改进: This knowledge will become part of you.

　　19. They cannot think clearly.

　　改进: They cannot think straight.

　　20. Money can improve their living standard.

　　改进: Money can improve their life.