氧乙炔焊接时,持焊炬的手不可戴手套,原因是()
A、手套易沾油渍,焊炬易滑落
B、手套易着火
C、将无法感受回火的热力
D、不方便焊接作业
参考答案:C
I never thought such a little child could succeed ______ with such a troublesome case.[ ]
A. in dealing
B. to deal
C. dealing
D. of dealing
三极管有_________、_________、________三种基本接线方式。