下左旋螺纹钻具时,绝不允许用()给左旋螺纹钻具上螺纹。
A. 转盘
B. 吊钳
C. 链钳
D. 液动大钳
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按照词法结构类型,语言可以分为()、()、()和()。
Cost of pipeline is very different of underground conditions. Is it right? ()
A. Not
B. Yes
C. They can’t compare
D. Not discussion in the paragraph
反密码子UGA所识别的密码子是:()
ACU
B. ACT
C. UCA
D. TCA