- 问题详情:Therearethousandsofcoralreefs(珊瑚礁)intheworld;Unfortunately,however,theyarenowinseriousdanger.Morethanonethirdareinsuchbadshapethattheycoulddiewithintenyears.__36__Herearethethreemaincausesdiscovered.Thefirstcauseispollutiononland.Thepoll...
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