---Sorry, I can’t work out this problem. ---Try again, please. It’s only ______ difficult.
_______yogurt do you need? -Three cups.
_____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.