对爆破效果有直接影响的岩石与空气、水或其他介质的界面称()。
参考答案:自由面
蒿芩清胆汤的发热特点是
A.日晡潮热
B.夜热早凉
C.恶寒发热
D.寒热如疟,寒轻热重
It is so cold in Antarctic that the penguins have to stand _______to each other to keep warm.
A.closely
B.closed
C.closing
D.close