1. Your arrogance has cost you many friends.2. Sheldon is the most egotistical, insufferable human being I've ever met.3. Since he was promoted, he's been drunk with arrogance.4. Do not think you are above everyone else; there are always people better than you.5. There were many pretentious people at the party.
 arrogant; haughty; cocky insolent egotistical pretentious口氣較重. egotistical 很貼切
The thesis of your essay is completely obscured by your flowery languge.