降产操作时，需要综合考虑的是（）。
A、降产速度
B、熔体泵出口压力
C、终聚釜真空
D、熔体粘度
参考答案：A, B, D
– At first he was not good at playing basketball but after a long time of training hard, he stood out.
– It’s easy to understand, ____________________.
A．Make hay while the sun shines.
B．Practice makes perfect.
C．The early bird catches the worm
D．Actions speak louder than words.
在含硫气井生产中，有那些方法来防止硫化氢腐蚀？
