It was playing computer games that cost the boy plenty of time that he ______ spent doing his lessons.
| A．might have | B．should |
| C．ought to have | D．could |
Our class adviser doesn’t doubt，in any case.___.we can overcome the difficulties in our study.Healways gives us a confident smile.
| A．how | B．whether | C．that | D．why |
It was never clear _______ the man hadn’t reported the accident sooner.
| A．that | B．how | C．when | D．why |
Barbara Jones offers to her fans is honesty and hapiness.
| A．Which | B．What | C．That | D．Whom |
It is uncertain____side effect the medicine will bring about，although about two thousand patients have taken it.
| A．that | B．what | C．how | D．whether |
The other day，my friend John drove his car down the street at _______I thought was a dangerous speed andsurprised everyone in the car.
| A．which，that | B．which，it | C．as，which | D．what，that |