I like to go shopping at the weekdays,_____the shop isn’t crowded.
| A．which | B．when | C．that | D．where |
We've worked out a method __________ our production can be greatly raised.
| A．with that | B．what |
| C．of which | D．with which |
Part of the reason Charles Dickens loved his own novel, David Copper field, was __________ it was rather closely modeled on his own life.
| A．what | B．that | C．why | D．whether |
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 |