bone 是可变名词(N-VAR ),即可数、不可数均可。用作不可数名词表示 “骨头” 这种物质,用作可数名词表示 “一块或几块骨头”。 N-VAR Your bones are the hard parts inside your body that together form your skeleton. 骨头 Many passengers suffered broken bones.(可数) 许多乘客骨折了。 The body is made up primarily of bone, muscle, and fat.(不可数) 人体主要由骨、肌肉和脂肪组成。