臀位易发生的并发症是
A．胎儿窘迫B．胎膜早破，脐带脱垂C．产后出血D．产褥感染E．胎足脱出
参考答案：B
After eight hours’ hard work, the firemen finally_________the forest fire.
A．put away
B．put out
C．put down
D．put in
主冷泄漏时技术参数有何变化？
