Answer:
Depending on the context you may consider antonyms to ostentatious such as reserved or modest. The word you are looking for is something like patina or tarnish.
Sort of easy, Flipping the bird is giving the middle finger, or swearing.
A lemon is a bad car.
3. I nearly swore at the man who made me annoyed by trying to sell me a duff vehicle
Answer:
We should honor the people that fought for our country like the army.