This printer is of good quality. If it ________ break down within the first year, we would repair it at our expense.
| A．would | B．should | C．could | D．might |
___you understand this rule, you will have no further difficulty.
| A．Once | B．At once | C．Only | D．Only then |
“Shall we stop for lunch _____ shall we drive on？” “Let’s stop for lunch, but the driver can’t drink _____ drive.”
| A．and, and | B．or, or |
| C．and, or | D．or, and |
____ you work, you must always serve the people heart and soul.
| A．Wherever | B．Whenever | C．Where | D．When |
____ makes mistakes must correct them.
| A．Who | B．What | C．Whoever | D．Whatever |
I’ll discuss it with you ____ you like to come.
| A．when | B．where | C．whoever | D．whenever |