根据 today’s birds of passage want 可定位到第一句最后一个短语 today’s birds of passage。而紧跟着的第二句话及第三句话中的代词 they, 毫无疑问指代的就是 today’s birds of passage。 其中第三句:They prefer to come and go as opportunity calls them,“他们愿意在机遇的召唤下来去自由。” 题干中的谓语是 want , want 即 文中 prefer to, 所以答案就是 come and go as opportunity calls them 的同义转换。答案可以确定是 D。题目4:The author suggests that the birds of passage today should be treated ( ).