眼球由哪几部分组成?
参考答案:
⑴眼球壁:①纤维膜(角膜、巩膜、角膜缘);
②葡萄膜(虹膜、睫状体、脉络膜);③视网膜。
⑵眼内容物:①房水;②晶体;③玻璃体。
工作面长度超过300m时,回采煤量可能大于准备煤量。
He’s watching TV He’s ______ to be cleaning his room.
A. known B. supposed C. regarded D. considered