He was of having asked such a silly question.
A.sorry
B.shame
C.ashamed
D.regret
答案:C
丹霞地貌又称红层地貌,是指在巨厚的红色沙砾岩上发育的()等特殊地貌。
A.方山
B.奇峰
C.岩洞
D.赤壁
互感器极性的试验方法有()
A.直流法;
B.观察法;
C.交流法;
D.比较法。