The bell ____ the end of the period rang and we had to stop our discussion
| A．indicating | B．indicated |
| C．to be indicated | D．being indicated |
One-third of the area ________ covered with trees. About seventy percent of the trees _______ been planted recently.
| A．is; has | B．is; have | C．are; have | D．are; has |
Neither Tom nor his parents ________ at home.
| A．is | B．are | C．has | D．was |
--It really shocked us that he should have made such_______ rapid progress in his study in such a short time!
--No surprising. He has been making _______ most of his spare time to study.
| A．a; the | B．a; / | C．/; the | D．/; / |
—Do you think I should accept his invitation, Jim?
—________If I were you, I certainly would.
| A．None of your business. | B．It depends. |
| C．Why not? | D．I don’t think so. |