Answer:
1. A complete or humiliating failure --- Fiasco
2. A place where military force is stationed for defense --- Garrison
3. Penetration for the purpose of subversive activity --- Infiltration
4. The act of restoring to a state of health and useful activity through training, therapy and guidance --- Rehabilitation
Explanation:
1- A fiasco is a disappointment or adverse outcome in a thing that was expected to happen well.
2- It is known as a garrison to the troops that protect and are destined in a palace, a castle, a fort, a warship, or any other determined place to defend it.
3- Infiltration is the action of getting behind enemy lines or simply in areas considered restricted by powers or foreign countries with different purposes, especially obtaining information.
4- Rehabilitation is the set of social, educational and professional measures designed to restore the subject in a situation of disability to the greatest possible capacity and independence.