(单选题)4: 下列器件中哪些不属于全控型器件。 A: 晶闸管 B: 电力晶体管 C: 电力场效应晶体管 D: 绝缘栅双极晶体管 ...
(判断题)20: 阳极是晶闸管主电路与控制电路的公共端。 A: 错误 B: 正确 ...
(多选题)14: 整流电路按变压器二次侧电流的方向分为: A: 单拍电路 B: 双拍电路 C: 桥式电路 D: 零式电路 ...
(单选题)8: 单相电流型逆变电路一周期工作波形中有()个稳定导通阶段和()个换流阶段。 A: 1,1 B: 2,2 C: 1,2 D: 2,1 ...
(单选题)2: 冲量指窄脉冲的()。 A: 高度 B: 频率 C: 面积 D: 能量 ...
(单选题)22: I forgot to ring up Mr. Wang yesterday, so I _______ today. A: can do it B: must do it C: had to do it D: must have to do it ...
(单选题)16: "I must be going now.""Oh, it's still early, _____ you stay a bit longer?" A: will B: wouldn't C: won't D: can ...
(单选题)4: — Congratulations! You won the first prize in today’s speech contest. — ____________________ A: Yes, I beat the others B: No, no, I didn’t do it well. C: Thank you D: It’s a pleasure. ...
(单选题)17: I needn't have taken a taxi. I______, it was only a hundred meters. A: could walk B: should walk C: could have walked D: ought to walk ...
(单选题)24: I don’t know why she avoids _______ her opinion on the subject. A: to give B: to be given C: giving D: being given ...