大多数海洋腹足纲软体动物在某些幼体阶段形成一种有纤毛的游泳器官。Most marine gastropod mollusks develop a ciliate swimming organ in certain larval stages.其中,双神经纲3种,瓣鳃纲68种,腹足纲80种.Among them there are 3 species of Amphineura, 68 species of Lamellibranchi...
The elevator creaked to a halt at the ground floor.电梯嘎吱一声停在了一层。The breeze grew in strength, the flags shook, plastic bunting creaked.微风渐强，旗帜舞动起来，塑料彩纸吱吱作响。The bed-springs creaked.床垫的弹簧嘎吱作响。...
空气稀薄清新，其间日光蒙眬，寒气逼人。The air was thin and crisp, filled with hazy sunshine and frost.他的政治生涯将近40年，其间起起伏伏。He had a chequered political career spanning nearly forty years.有过交火，其间那名持枪歹徒受伤了。There was an exchange of fire during ...