( )31. It takes us ____ hour or more to go to my hometown by _______ train.
A. an; a B. a; an C. a ; / D. an; /
( )32. —When will the second class begin? — _______ two minutes.
A. For B. At C. In D. After
( )33. — Could I use your eraser for a while? — Yes, of course you ________.
A. could B. can C. will D. should