VOA慢速英语:Australia’s Great Barrier Reef Threatened

species – n. a group of animals or plants that are similar and can produce young animals or plants; a group of related animals or plants that is smaller than a genus

coral – n. a hard material formed on the bottom of the sea by the skeletons of small creatures

algae – n. simple plants that have no leaves or stems and that grow in or near water

aerial – adj. taken or seen from an airplane

pristine – adj. not changed by people; left in its natural state

survey – n. an act of studying something so as to be able to make a judgment about it

unfold – v. to happen as time passes