对有部分破裂和脱落危险的砌块，（）起吊。
A.建议
B.允许
C.严禁
D.特殊情况可以
参考答案：C
The reporter said that the UFO ________ east to west when he saw it.[ ]
A. was traveling
B. traveled
C. had been traveling
D. has traveled
下列( )指标表征硅酸盐水泥的化学性质。
A．MgO
B．SO3
C．CaO
D．烧失量
