PN结具有单向导电性,可通过在PN结两端加正向或反向电压来证实。()
参考答案:对
Many people in China have never dreamed of ________ a chance for them to learn to drive after their
retirement.[ ]
A.being
B.there
C.there to be
D.there being
《商业银行并购贷款风险管理指引》规定,并购贷款期限一般不超过()年。