找 grammer mistakes

1) Be confident in yourself.
2) Wait for the bus.
3) From my point of view.....................
4) I suggest that you can buy second-hand clothes.
5) Real friends are people who support you all the time.
6) Part-time jobs can let you obtain work experience.
7) Your friends won't care if you are fashionable or not.
8) When will you be back to school?
9) It is not worth doing so.
10) Working at night is not suitable for you. You don’t have enough time for rest.
11) You should remember not wasting money on clothes.
12) Real friends will be concerned about your inner beauty.
13) Working on the night shifts to earn money is not a bad thing for you.
14) You blindly follow the trend.
15) You need not care about the opinions of the bad friends.
16) Wanting to be fashionable is a common problem of teenagers.
17) Spending a lot of money on your clothes is unwise.
18) This can prevent you from spending too much money.
19) No one could hear the alien. It is just like talking to myself.
20) You may be expelled.
21) You are just a teenager.

2011-04-10 01:59:00 補充：
It is my understanding that you only want 把正確的寫法整句寫一次.
For example
20) maybe is an adverb, not a main verb.
21) teenage is an adjective, not a noun.
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