1. He looked out of the window, _________the landscape of the countryside. 
A. obscuring B. broadening C. surveying D. impressing
2.The speech is scheduled at 3 o.clock this afternoon. The students are __________the assembly hall now.
A. filing into B. jumping C. enter D. come into
3.His father was quite stubborn and it was almost impossible to __________ him of his mistakes.
A. prevent B. prohibit C. convince D. persuade
4._________ houses for a few weeks is a good way of having a holiday.
A. Exploring B. Extending C. Exchanging D. Registering
5.All the materials collected for the research project on pollution are ___________ to all the seniors at this college.
A. explored B. available C. registered D. exchanged