设备灌浆料通常由设计选用,设计未提出要求时,宜用无收缩混凝土或( )。
A.普通混凝土
B.微膨胀混凝土
C.高强度混凝土
D.环氧砂浆
参考答案:B
The red socks _____ two dollars. [ ]
A. am
B. is
C. are
D. do
The thief was apprehended, but his accomplice had disappeared.
A.people who saw him
B.the person who helped him
C.guns and knives
D.stolen goods