按电晕放电的要求,输电线路导线的最小直径是如何规定的?
参考答案:
Stone seldom, _______, refuses to help others when they turn to him, for he is only too ready to do so.
A.if never
B.if not
C.if ever
D.if any
布鲁纳认为学习包括获得、转化和()三个过程。