An awful accident_____，however，occur the other day.
| A．does | B．did | C．has to | D．had to |
With the monthly test approaching, Paul is busy preparing for it, only_____ playing basketball to relax a bit.
| A．occasionally | B．seldom |
| C．rarely | D．frequently |
According to the new class rule, students foundcellphones in the classrooms will be asked to leave the rooms immediately.
| A．use | B．to use | C．using | D．having used |
It is a widely held belief____honesty and integrity(正直) are the qualities ____ a leader should be made of.
| A．that; that | B．that; what |
| C．which; what | D．what; that |
Scientists believe that it might be several years ______ the medicine can be used on human beings.
| A．since | B．when | C．before | D．until |
I used to think Jack was not a man to count on, but I have changed my ______ as he saved an old man from the fire.
| A．state | B．condition |
| C．situation | D．position |