Do Now

Do Now: Can you solve this riddle?

I am free, but priceless.

You cannot own me, but you can use me. 

You can't keep me but you can spend me and

once you lose me, you can never get me back. 

What am I?

Today Teacher ask us a trick question in order to let us relax. I think it for really a long time. I think if it is tissue, toy, book, pencil, test, or other things. To my surprise, the answer is money.