在概念形成过程中,_____和比较起着重要作用。
参考答案:变式
Unsatiafied _____ with the payment, he took the job just to get some work experience. [ ]
A. though was he
B. though he was
C. he was though
D. was he though
为什么要在氯乙烯压缩机操作中防止入口管线抽负压()
A、容易抽入空气而发生爆炸事故
B、避免使压缩机吸气能力降低
C、防止发生液击事故
D、防止压缩机故障