21.  For example, if you like literature, you can read many books in the library, if you are interested in physics, you can spend much time on it although you are in biology department .

22.  I should spend enough time not only in studying, but also in thinking of my daily housework which was done by my parents before.

23.  To the second , it will cause you spent your time in waiting .

24.  Someone think it's very efficient that you spend little time doing things better.

25.  So at last you not only don't finish this matter , but also you spend more time.

26.  Finally, they don't buy good tickets but they spend more time to go out of the crowded people.

27.  Otherwise, they can't spend more time on studing new technology.

28.  If they didn't spent the long time ,ever their lives, they couldn't do anything in science.

29.  So they don't spend much time in studding how to work well.

30.  If his work has nothing with he studied in school, he has to spend much time studying new knowledge .