31．Chicago lies _________ the two rail roads are connected．
| A．where | B．wherever | C．in the place | D．in which |
—What qualities does a person need to become an astronaut?
—He ________be knowledgeable，independent and creative.
| A．can | B．may |
| C．would | D．should |
Li Gang was required to apologize ________the people present at the meeting________what he had done.
| A．for；by | B．with；about |
| C．to；for | D．at；with |
—Have you heard that George quit his job?
—Yeah, but I can't________why he did so.
| A．put out | B．figure out |
| C．carry out | D．send out |
—Tony, you must have noticed the student who broke the glass.
—I'm sorry.I________attentively.
| A．studied | B．was studying |
| C．am studying | D．would study |
—Sorry for the delay.I got lost in the mountain.
—That's OK.You're safe and that's what________.
| A．does | B．works |
| C．stays | D．counts |