Topic is the same as your website, but the info needs to be hot off the press! For example, if your website is about sea turtles, get on Google and search the news sites for something new and exciting going on with turtles. Then, summarize the info onto your blog.
Your blog post should be at least 5 sentences.
But, blogs aren't just for sharing news. They are for sharing your unique, personal take on the news. So please share your opinions and emotions about the topic.