题目内容：

Ⅲ. Find the only mistake in each line and correct it.

 

Time flies and I will say goodbye to my junior school

very soon. Many unforgettable events happened                21. 1.

in the past three years. Lucky enough, I have good               22. 2.

teachers and friendly classmate. I still remember once          23. 3.

when I didn’t do well in my math exam, I have got really         24. 4.

upset. My teachers gave me some advices on my study.         25. 5.

My classmates told me I should never lose confident.          26. 6.

I persuaded by their encouraging words and I studied           27. 7.

even harder. Finally, I improved myself a lot with our help.     28. 8.

Now I believe that failure is the mother to success,             29. 9.

which is that my teachers and my classmates told me.             30. 10.