Sam spends two hours _______ his homework every day.
Our classroom is very dirty ,let’s _____it_______.
Whose book is that ? It _______belong to Linda .Look !Her name is on it .
________I smoke here ? ----No. you can’t.
.---______you swim ? ----Yes, but I’m not good at swimming .
Billy is a nice boy . he knows a lot , but he never ________.