Some people are bad at recalling names and faces, so it's possible that they have a condition called face blindness, ______ people suddenly have trouble recognizing family members, friends or even themselves．
| A．for which | B．which | C．where | D．of which |
The boy wanted to ride his bicycle in the street, but his mother told him _______.
| A．not to | B．not to do |
| C．not do it | D．do not do |
We looked everywhere for the keys, but they are nowhere _______.
| A．to find | B．to have found |
| C．to be found | D．being found |
He was reading his book, completely _______ to the world.
| A．lost | B．losing |
| C．to lose | D．to have lost |
She looks forward every spring to _______ the flower-lined garden.
| A．visit | B．paying a visit |
| C．walk in | D．walking in |
Anyone _______ bags, boxes, or whatever, was stopped by the police.
| A．seen carry | B．seen carrying |
| C．saw to carry | D．saw carrying |