In the forest we observed some trees____the leaves were black with disease.
| A．where | B．of which | C．in which | D．whose |
---You were brave enough to raise objections at the meeting.
---Well, now I regret ____ that.
A. to do b. to be doing C. to have done D. having done
Unless ___ to speak，you should remain silent at the conference．
| A．invited | B．inviting | C．being invited | D．having invited |
The building ________ will be used as our new library.
| A．is being constructed | B．built | C．under construction | D．to build |
The medicine has a strong side ________ on our health though it works well.
| A．influence | B．effect | C．affect | D．impact |
The town official broke ________ for working over time in the search for the trapped people after the earthquake.
| A．out | B．away | C．down | D．into |