fall back on["~에 의지하다"]

fall back on

: to have a second plan if a first plan doesn't work 

  "~에 의지하다"
A.

Sally wants to find her own apartment and to try living by herself.

If this becomes too expensive,

she can always fall back on her family and live with her parents.

B.

Stephanie is a postal clerk, but now she's also taking a course in computer programming.

She hopes to get a high-paying job in computers.

If she doesn't , she knows she can fall back on her Post Office job. 

[주] 

: a postal clerk : a clerk who works at the post office