Mr. Smith couldn’t open the door because his naughty boy _______ it from the inside
| A．would lock | B．was locking |
| C．has locked | D．had locked |
Of one thing I am certain _____ hard work contributes to good results.
| A．as | B．what | C．which | D．that |
A decision has been made ________ the new school building be built next month.
| A．why | B．how | C．whether | D．that |
We agreed to accept__________they thought was the best professor in the college.
| A．whatever | B．whomever | C．whichever | D．Whoever |
There is no possibility, I guess, _____our exam will be put off.
| A．what | B．which | C．that | D．whether |
Far from perfect though this trip is, I think it’s well worth _____ we paid.
| A．that | B．what | C．which | D．How |