The island, ___ to the mainland by a bridge, is easy to go to.
| A．joining |
| B．to join |
| C．joined |
| D．having joined |
If you ___ smoke, please go outside.
| A．can |
| B．should |
| C．must |
| D．may |
I wasn’t sure if he was really interested or if he ___ polite.
| A．was just being |
| B．will just be |
| C．had just been |
| D．would just be |
As he reached ___ front door, Jack saw ___ strange sight.
| A．the;/ |
| B．a;the |
| C．/;a |
| D．the;a |
What would have happened, ___, as far as the river bank?
| A．Bob had walked farther |
| B．If Bob should walked farther |
| C．Had Bob walked farther |
| D．If Bob walked farther |