电视发射机首先将视频信号调制成为（）信号，再经调制到高频信号后通过天线发射出去。
参考答案：固定中频
-You've won the first prize in the English speaking contest. Congratulations!
-_______.
A．It's nice of you to say so
B．I am really lucky
C．No one else could do it
D．Oh, not really
搭肩试验用于诊断（）
A.网球肘
B.肩关节脱位
C.肱二头肌长腱滑脱
D.冈上肌腱断裂
E.肱骨外科颈骨折
