The United Nations is trying to free the world________the threat of war.
| A．at | B．in |
| C．by | D．from |
22. She always ____ her opinion ____ facts.
| A．depends, on | B．bases, on | C．put, into | D．bases, by |
21. Every morning, the fish mongers stood there ______ with the fishermen for fishes.
| A．to argue | B．to talk about prices | C．bargaining | D．Discussing |
20. When Jack arrived, he learned Mary ____ for almost an hour.
| A．had gone | B．had set off | C．had left | D．had been away |
19. They didn't _____ the wedding because of a heavy rain.
| A．join | B．take part | C．attend | D．Appear |
18. Don't worry! He ____ no attempt to leave. He will stay here to help you.
| A．made | B．got | C．had | D．Tried |