Please excuse me _______ your letter by mistake.
The skirt is too large for me.Would you show me ___ one ?
The children are giving their classroom a good cleaning, ___ are sweeping; ___ are mopping.
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.