听骨韧带主要有_____、_____、_____、_____、_____等,将听骨固定于鼓室内.
参考答案:锤上韧带、锤前韧带、锤外侧韧带、砧骨上韧带、砧骨后韧带、镫骨环韧带
简述微生物培养基的种类和灭菌操作?
The most important program on any computer is ______.
A.Office 2000 B.Virus C.software D.Operating system