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National parks are places to be treasured—places 【小题1】 the country locks away the very best it has to offer for everyone to enjoy. Not all famous national parks are on land. One good example is the Great Barrier Reef Marine Park in Australia. 【小题2】 (stretch)over 2,300 kilometers, the Great Barrier Reef is considered one of the natural 【小题3】 (wonder)of the world. The park was created in 1975 to protect the reef from overdevelopment and fishing. Unfortunately, the biggest danger to it is global warming, 【小题4】 park management cannot stop.