--- Hi ,Tracy, you look tired.--- I am tired. I ____the living room all day.
Tom,Bob and Betty have arrived, but ___ students haven’t yet.
He has three pencils.____ is red, ___is blue, and ____ is green.
.She has three brothers.___ is a doctor, ___ are PLA men.
I have two bicycles, ____ is made in Guangzhou;____ is made in Shanghai.
___ took them quite some time to finish the job.