阅读理解。 Years ago, if a teenager had some problems in her life, she might write in her diary. Now a teenager with the same problems might go onto the Internet and write about them in a blog (博客). In many ways, a diary and a blog are almost the same. So, what makes a blog different from a diary? 1. Usually, a teenager treats her diary like a book full of secrets. Both diaries and blogs tell what happened to the writer that day. I have a little sister, and sometimes I go online to read her blog. She writes about things like waking up early for swimming practice and not studying enough for her chemistry exam. 2. Then, after I finished writing, I would hide my diary in a secret place because I was worried that my sister might read it! Because a blog is such a public way of writing, it has both good and bad points. 3. If I am angry with a friend during school and write something bad about her in my diary, she will never know. However, if my sister writes something bad about a friend, that friend may read her blog and get angry. 4. A blog has good points, of course. People choose to write in blogs because they know that their friends will read what they write. If I am feeling sad one day and write in my diary, 'Nobody cares about me', no one will know about it. However, if my sister writes the same words in her blog, her best friends will quickly reply and tell her how much they like her. Blogs help people stay in contact (联系) with their friends and know what the people around them are doing. If people are careful about what they write, blogs are a very good way to write about everyday life. However, I still prefer my old diary! 根据短文内容，从方框内选出适当的选项填入文中空白处，使短文内容完整正确。 A. So we have to be very careful of what we write. B. When I was her age, I wrote about the same thing, but only in my diary. C. The biggest problem with a blog is that anyone can read what you write. D. The biggest difference is that a blog is much more public than a diary. 5. Which one is NOT the writer's idea? [     ] A ． A diary is safer than a blog. B ． A diary and a blog are almost the same in many ways. C ． Blogs can help people stay in contact with their friends. D ． Blogs are the best way to write about everyday life.