产生系统误差的原因主要是测量仪器和工具的构造不完美或校正不准确。( )
参考答案：对
As a result of the serious earthquake, two-thirds of the buildings in that area _______.
A．need repairing
B．needs to repair
C．needs repairing
D．need to repair
铁路运输的缺点主要有( )。
A．资金密集
B．固定投资大
C．营运弹性大
D．车站固定
E．不适宜紧急运输
