题目内容：

短文改错（10分）

I like riding my bike. Though it is not very new, but it is my best friend. I find very convenient to go anywhere with a bike. Riding gives me not only exercises but also pleasure. I use my bike almost in summer when the weather is warm and dry. It can be very pleasant in winter when it is cold and rain is pour down. It can also be very dangerous. Of course I will be very carefully on my bike. In fact, accidents are not the only problem. Once I went to bookstore on my mother’s bike to buy some books and come out to find the bike missing. Now I have two strong lock.