11. ______________ may be preferable to ______________, but it also suffers from the disadvantages that ______________.
        12. but i don’t think it is a very good way to solve ______________. for instance, ______________. worst of all, ______________.
        13. there are many ways to ______________. first, ______________. second, ______________. third, ______________.
        14. on the contrary, there are some people in favor of ______________. they believe ______________. moreover, they think ______________.
        15. there are several measures for us to adopt. first, we can ______________, there are a number of advantages of ______________. another solution is to ______________.
        16. it is high time that something was done about it. for example, ______________. in addition, ______________. all these measures will certainly ______________.
        17. there are some other people, who ______________. their reasons are different, something for ______________, sometimes for ______________, and sometimes simply for ______________.
        18. ______________ is necessary and important to our country’s development and construction. first, ______________. what’s more, ______________. most important of all, ______________.