＿＿＿used to be thought that the earth was square.
| A．He | B．What | C．It | D．That |
31. We______ on the project for three hours. Let’s have a rest.
| A．are working | B．have been working | C．worked | D．had worked |
My grandparents asked me to go and see them whenever______.
| A．I am convenient | B．I will be convenient |
| C．it is convenient | D．it will be convenient |
. ______some people dislike may be others’ favorite.
| A．Whether | B．What | C．That | D．How |
Studies show that office workers are more ______to suffer from backache because they always sit before computer screens for long hours.
| A．surely | B．likely | C．probable | D．possible |
. She_____ Japanese when she went to Japan for holiday. Now she can speak it freely.
| A．picked up | B．turned up | C．made up | D．took up |