短文改错,改10处,One day a group of us had a game of football on th

One day a group of us had a game of football on the way to school.One of the older boy（boys) pushed me and i fell over torn(tearing) my jeans very badly.I had to go home to change so i arrive (arrived)very late for school.I expected to get on trouble about it,and(改成but) nothing happened.After class,the teacher asked me who had pushed me.Of course i answered"I can't say."Then i asked how he knew about them(it).He said,"Alex told me what was(去掉was,改成had) happened,but he didn't say who pushed you."Then he told me to be more carefully (careful)in (加上the)future.That afternoon i walked home with Alex and thanked him of (去掉of,或者改成for)what he had done.No matter what people said about Alex,i knew he was(a) true friend.