______, I think, and all the problems could be settled.
| A．If you make more efforts |
| B．Making more efforts |
| C．A bit more effort |
| D．To have made more efforts |
The town’s drinking-water _____ with prim chemicals at present.
| A．contaminates | B．is contaminated |
| C．is being contaminated | D．has been contaminated |
I feel that it was time for me to ____.
| A．take actions | B．take an action | C．take the action | D．take action |
They their side of the field very well.
| A．defended | B．protected |
| C．keep | D．prevent |
Her father gave her the ___ of going on to college or starting to work.
| A．chance | B．opportunity |
| C．alternative | D．possibility |
He soon found himself his new co-workers.
| A．in harmony of | B．in the harmony of |
| C．in harmony with | D．in the harmony with |