A blackbird flew down and perched on the parapet outside his window.一只乌鸫飞下来，停在他窗外的矮墙上。The blackbird's nest contained four eggs.黑鹂巢里有四个蛋.The blackbird had a quick, wary look in case the cat was anywhere around.这只乌鸫迅速...
The abnormality mitral stenosis was in myocardium, not in the valve.二尖瓣狭窄的病变是在心肌而不是在瓣膜.Valvular heart disease, usually aortic and mitral insufficiency, can complicate a variety of systemic diseases.瓣膜性心脏病, 以主动脉瓣及二尖瓣闭锁不全为...