电联结线应留有一定的裕度，适应接触线和承力索因温度变化伸缩的要求。
参考答案：对
Seeing her father come back, ______________.
A．tears ran down her cheeks
B．Her tears ran out
C．she burst into tears
D．She burst into crying
建设项目的环境管理原则是什么？
