.When she came out, Mary looked a bit tired because she _____the house.
| A．cleaned | B．was | C．had cleaned | D．had been cleaning |
I can’t find a proper person _______ I can depend to help me.
| A．on which | B．on whom | C．up which | D．up whom |
.Her explanation to the question made all of us ________ .
| A．to confuse | B．confusing | C．confuse | D．confused |
I have read the material several times it doesn’t make any ______ to me.
| A．sense | B．importance | C．meaning | D．significance |
.It is ________ that people will not agree with what the manager at the meeting.
| A．certainly | B．sure | C．certain | D．surely |
The problem is _______ we can arrive there before 6:00 tomorrow morning.
| A．which | B．whether | C．when | D．that |