Question

fix the one word that is used incorrectly.
airlines dont usually loose their passengers luggage, but when they do,
most bags are found and returned within forty - eight hours.

Explanation:

The word "loose" is an adjective meaning not tight, but the sentence requires a verb meaning to misplace. The correct verb form is "lose".

Answer:

Replace "loose" with "lose". The corrected sentence is: Airlines don't usually lose their passengers' luggage, but when they do, most bags are found and returned within forty-eight hours.