Answer:
I am round. I have only one line. Circle is not my name indeed. What am I?
We are little airy creatures all of different voice and features one of us in glass is set. One of us you'll find in jet. Another you may see in tin. And the fourth a box within. If the fifth you should pursue it can never fly from you.
I am an object which is used in baseball. During the day I can't be seen at all. What am I?
I must be broken before you can use me. What am I?
If you drop me, I'm sure to crack. Give me a smile and I'll always smile back. What am I?
It has no top or bottom, but it can hold flesh, bones, and blood all at the same time.