天鹅湖歌曲:how does a clock work?

how does a clock work? how does a clock work? how long does a basketball match last How many sides does a circle have how fast does a balloon travel? How fast does a balloon travel? how many legs does a spider have How many sides does a house have? how fast does a balloon travel? How about an overplance?How about a space shuttle? 脑筋急转弯:How many sides does a circle have?