Big Ben is not the name of a man. It's the name of a big clock in London. This clock has four faces. So, no matter(无论)where you stand, you can read the time on the face of Big Ben. Each face is the size of a bus. The hands are about four metres long. If you go to London, you may want to visit the Houses of Parliament(英国国会大厦). In that place you will find Big Ben sits at the top of the clock tower in the Houses of Parliament. You will probably hear it and see it. The big clock makes such a loud noise. It goes every quarter of an hour. Big Ben has been the most famous symbol(标志)of  London

常见的环节动物有____、____、____ ；常见的腔肠动物有____ ；乌贼属于____，虾属于____ ．

向日葵在生活过程中要呼吸，需要（）