ненадійний på engelsk:

Her health remained precarious, despite the treatment. a precarious mountain trail

a precarious situation

People smoke to relax and forget their cares, but ironically, in terms of health risks, smoking is far more precarious than either mountain-climbing or skydiving.

The museum is in a financially precarious position.

The world is a precarious place.

Your position is precarious

The lorry was lodged in a very precarious way, with its front wheels hanging over the cliff.