四边孔
参考答案:
又称四边隙,其上界为小圆肌、肩胛下肌,下界为大圆肌,内侧界为肱三头肌长头,外侧界为肱骨外科颈,内有腋神经和旋肱后血管通过。
What is Tom doing now
A. He is borrowing some books.B. He is reading some books.C. He is returning some books.
下列说法错误的是
A.木炭在氧气中剧烈燃烧,生成黑色固体
B.硫在空气中燃烧,生成有刺激性气味的气体
C.铁丝在氧气中燃烧时,火星四射
D.红磷在空气中燃烧时,产生大量的白烟