If the American government the expert’s suggestion, the world economy would not be in such a mess now.
| A．followed | B．follows |
| C．should follow | D．had followed |
—I wonder if I could use your phone?
— ________.
| A．Go ahead | B．Never mind | C．That’s right | D．Take it easy |
Do you have any idea ________ is actually going on in the classroom?
| A．that | B．what | C．as | D．which |
— Can you give me some advice on what I said just now?
—Sorry. My mind ________.
| A．is wandering | B．was wandering | C．has wandered | D．had wandered |
Chemicals in the body ______our food _____ into useful things．
| A．break, into | B．break, up | C．break, down | D．break, off |
—Peter looked tired and a little absent-minded in class．
—He _____ too late．
| A．may stay up | B．could stay up |
| C．should have stayed up | D．must have stayed up |