在制冷系统中常用的安全设备有安全阀、熔塞和（）等。
A.紧急泄氨阀
B.爆破片
C.压力表
D.液位计
参考答案：A
按要求完成下列题目。
1. Can you play the v_______?
2. He can d_______ and sing.
3. I want to join the art c______.
4. Does he play the p_______ every day?
5..He can _______(play) the drums.
6. Can he play the guitar ________(good)?
试述TPI硫化过程表现出的三阶段特征。
