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来源:雅诚德英语网
Coral reefs are formed by deposits of calcium carbonate left by successive generations of tiny polyps which feed off plankton.
珊瑚礁是由历代以浮游生物为食的小水螅所遗留下来的碳酸钙沉积物而形成的。
Coral reefs are formed by deposits of calcium carbonate left by successive generations of tiny polyps which feed off plankton.
珊瑚礁是由历代以浮游生物为食的小水螅所遗留下来的碳酸钙沉积物而形成的。