The document provides examples of expressions used to congratulate someone in both formal and informal contexts. For formal congratulations, phrases include "Congratulation on...", "I must congratulate you on...", and "Let me congratulate you...". Informal expressions are shorter such as "Well done", "Nice one", and "Fantastic!". A few examples are given of people using congratulatory expressions when someone gets a boyfriend, graduates, does well on an exam, or gets a scholarship.