电流互感器工作时,其二次侧不允许短路。
参考答案:错
若奇函数f(x)定义域为R,且x≥0时,f(x)=x(x+1),则x∈R时f(x)的解析式为______.
The door opened and _____ a middle-aged woman with fashionable clothes. [ ]
A. came in
B. in came
C. did come in
D. in did come