锅炉清洗方法有机械清除法和化学清洗法两种，干熄焦锅炉一般常用（）清洗。
参考答案：化学清洗法
I don’t want _______ like I’m speaking ill of anybody, but the manager’s plan is unfair.
A．to sound
B．to be sounded
C．sounding
D．to have sounded
The fact __ in the past few years proves that out Party’s policy is correct.
A．that great achievement was made
B．which great achievement were made
C．what great achievement have been made
D．that great achievement have been made
