Where do the two railroads connect [link up]?

两条铁路在何处连接？

The ultimate intention is to link up all the cars on the road via WiFi by setting up a WiFi-enabled sensor in a car.

最终的目标是把道路上所有汽车通过无线网络联系起来，在车内安装支持 WiFi 的传感器。

The two spacecraft will link up in orbit.

两艘宇宙飞船将在轨道上对接。

They have planned to link up the two areas by telephone.

他们计划用电话把两个地区连接起来。

They also link up with groups based in the Waziristan region of Pakistan.

他们也会和以巴基斯坦瓦基里斯坦地区为根据地的武装团伙联合行动。