the _____ observation, of the absence of grazers (食草动物)in areas of high phytoplankton(浮游植物群落)_______, led hardy to propose his principle of animal _______ , which _______ that phytoplankton produced a repellent(驱虫剂) that excluded grazers from regions of high phytoplankton concentration.
[参考译文]相反的观察，即在浮游植物群落高度集中的地方缺乏食草动物的现象，使哈笛提出了他的“动物排除”理论，该理论假设浮游植物群落能产生一种驱虫剂赶走在浮游植物高度集中区域内的食草动物。
参考答案：converse,concentration,exclusion,hypothesized
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“the biggest_______project of this century”, explained french president francois mitterand in january, 1986 as he and then british prime minister margaret thatcher______announced that the two countries would finally overcome ancient quarrels and ______ and _____ a link across the narrow channel _____ them.
[参考译文]1986年1月，法国总统弗兰西斯· 密特朗解释说：“这是本世纪最大的建设项目。”当时，他和英国首相玛格丽特·撒切尔一起宣布两国将克服一直以来的争论和偏见，铺设一条横穿分隔两国的狭长海峡的地下隧道。
参考答案：construction,jointly,prejudices,forge,separating