What is the range of the pelagic environment?水层环境的范围是什么?What is the origin of pelagic oozes?远洋软泥的来源是什么?Plankton and nekton are pelagic organisms.浮游生物和自游生物都是海面的生物....
She gave them extra helpings of ice-cream.她又给了他们几份冰激凌。You greedy pig! You've already had two helpings!你这个馋嘴！你已经吃了两份了！He had two helpings of pudding.他吃了两客布丁....