标题: 一道纠结的题请教~~ [打印本页] 作者: iamBB 时间: 2011-9-12 14:56 标题: 一道纠结的题请教~~ Dolphins lack vocal cords, nevertheless creating sounds: a complicated system of whistles, Squeaks, moans, trills, and clicks are produced by sphincter muscles inside the blowhole. A. nevertheless creating sounds: a complicated system of whistles, squeaks, moans, trills, and clicks are produced by B. nevertheless creating sounds: they produce a complicated system of whistles, squeaks, moans, trills, and clicks with C. but they do create sounds, producing a complicated system of whistles, squeaks, moans, trills, and clicks with D. but they do create sounds, a complicated system of whistles, squeaks, moans, trills, and clicks being produced E. but nevertheless creating sounds: a complicated system of whistles, squeaks, moans, trills, and clicks produced by