He's completely unreliable.他根本靠不住。

Diplomats can be a notoriously unreliable and misleading source of information.外交官可能会提供一些靠不住的误导性信息, 这是众所周知的。

It's a nice car, but a bit unreliable.这是辆好车, 但性能不太稳定。

He had an unreliable car.他的车性能不稳定。