inutilisable

In a sentence

• Cet ancien ordinateur est inutilisable à cause de sa vétusté.

  This old computer is unusable due to its obsolescence.

  Here, "inutilisable" is used as an adjective to describe the computer as being in a state where it cannot be used.

• La route est inutilisable après l'accident, il faut trouver un autre itinéraire.

  The road is unusable after the accident; we must find another route.

  In this case, "inutilisable" is applied to describe the condition of the road being unsuitable or impossible to use.

• Ce tournevis est inutilisable pour visser les vis de ce format.

  This screwdriver is unusable for screwing screws of this format.

  "Inutilisable" here indicates that the screwdriver cannot be used for the intended purpose or task due to a mismatch in specifications.