. _____in a science competition, the three students were awarded scholarships totaling $ 21, 000.
It is reported that the United States uses ________ energy as the whole of Europe.
It was along the Mississippi River _________ Mark Twain spent much of his childhood.
At the meeting place of the Yangtze River and the Jialing River __________, one of the ten largest cities in the world.
Some insects __________ the color of their surroundings to protect themselves.
We promise ________attends the party a chance to have a photo taken with the movie star.