Bill Gates has created a wonderful “window” ______ people can surf the Internet freely.
With some effective measures __________,the traffic condition of the city has been further improved.
Environmentalists urged that more effective measures __________ by the government to reduce the pollution.
Do you think that bridge __________2,000 meters long? It doesn't appear __________ long.
Now in order to __________ lungs, you have to start breathing deeply and cough more effectively.
__________ all over the mountain __________ wild flowers.