In order to finish the experiment successfully, the professor always _________, for every day the light in his room didn’t go out until 4 a.m.
“____either you or he to go there?” “_____is.”
____of the land in that district ____covered with trees and grass.
Burning all the lights in the classroom will be a great______ on electric power.
If you build a house with good_______ , it will last long.
After many years’ waiting, Chinese people______ realized their dream to hold the Olympic Games.