当大部分声能进入材料,而()能量很小时,表明材料的吸声性好。
A、传递
B、表面
C、反射
D、存储
参考答案:C
施工进度计划一般用图表表示,经常采用横道图和网络图两种形式。
My little brother was born __a rainy day __summer and our family name is exactly “Xia”. So we call him “Xia YU”.
A.on, at
B.on , in
C.at, in
D.in, on