导线分裂结构主要由导线的电晕特性和其对导线的本身机械特性( )、金具及杆塔的影响来确定。
A.振动; B.温度; C.舞动; D.覆冰。
参考答案:A,C,D
(2012·驻马店高二检测) Here we found little snow, as most of it seemed _______ blown off the mountain.
A.that it was
B.to be
C.to have been
D.that it had been
奶牛的干奶期一般为()天。
A、40
B、100
C、60
D、20