When Miss Green began to something, the children stopped and became quiet.
Using many symbols makes ______ to put much information on a single map.
The policy of the mainland is very clear and straightforward,and the key problem is ______ the leaders of Taiwan will accept it.
After five years of preparation,Shanghai presented the world ______ many said was the greatest Special Olympics.
At the meeting they discussed three different ______ to the study of maths.
Studies show that the things that contribute most to a sense of happiness cannot be bought,______ a good family life,friendship and work satisfaction.