In order not to be disturbed, he spent two hours ____ in his study.
| A．locking | B．to lock | C．locked | D．being locked |
--- You didn’t tell your parents the date of our graduation ceremony, did you?
--- No, but I ____. My sister had told them.
| A．didn’t need to | B．needn’t have | C．couldn’t have | D．shouldn’t |
The boss took no notice of the suggestion given by the clerk that the new technology ____ the problems on conveying the products.
| A．be applied to solve | B．be applied to solving |
| C．must be applied to solving | D．must be applied to solve |
He couldn’t continue to live such a poor life, so he left home, ____ not to come back if he couldn’t get rich.
| A．determining | B．determined | C．determine | D．being determined |
The beautiful lady was at ____ loss when ____ word came that she was forbidden to drive for speeding too many times.
| A．a; a | B．the; a | C．the; the | D．a; / |