* Proper nouns are specific names of people, places, or things. They are always capitalized.
* Examples: John Smith, London, the Eiffel Tower.
* "President of the student government" is a common noun phrase. It describes a position or role. Since it's not a specific name, it's not capitalized.
However, if you are referring to a specific person holding that position, then you would capitalize their name. For example:
* "John Smith is the President of the Student Government."