短文改错（共10小题；每小题1分，满分10分）
改正下面短文中的错误。对标有题号的每一行作出判断：如无错误，在答题卡该行右边横线上画一个勾（√），请在有错误的地方增加、删除或修改某个单词。
注意：1.每处错误及其修改均仅限一词；
2.原行没有错的不要改。
Time flies as an arrow. I'm already in the second half        1.______
of senior grade 3 before I realized it. It is only a little more        2.______
than three months before I graduate middle school. At       3.______
the present, I'm busy reviewing my lessons in order to      4.______
take the college entrance examination. I hope to go to        5.______
Beijing University, that is one of the best universities not    6.______
only in China but also in the world. I'll try my best to turn 7.______
my dream to reality. Most of my classmates are also 8.______
studying very hard to realize our wishes. I do believe everyone   9.______
will be able to enter a very good university and college.         10._____