Mr. Wang is a nice teacher. He often helps his students with _______ physics after school.
_____mothers both work in the same hospital.
In the street I met the professor_______gave us a talk last week.
-Would your brother go for a picnic this Sunday7 -If I don't go,____.
You must______your cigarette when you are at the gas station.
Her grandparents are still in good health_____they are over eighty.