Such is human nature that many people don’t value things they possess until they’re lost them.
| A．不填；不填 | B．不填；the | C．the;不填 | D．a; the |
It has been proved __________ eating vegetables in childhood helps to protect you against serious illnesses in later life.
| A．if | B．that | C．when | D．because |
The reason why he was sent to the hospital was __________ he was ill.
| A．that | B．because | C．since | D．why |
The speaker spoke of some writers and some books __________ were popular then.
| A．/ | B．that | C．which | D．who |
I refuse to accept the blame for something __________ was someone else's fault.
| A．who | B．that | C．as | D．what |
There is clear evidence __________ the most difficult feeling of all to interpret is bodily pain.
| A．what | B．if | C．how | D．that |