un adjectif
A describing word: grand, gentil, curieux.
l'accord
Agreement: changing the adjective to match the noun (masculine or feminine, singular or plural).
le portrait
A description of what a person or character looks like and is like.
le physique
What someone looks like (tall, grey fur...).
le caractère
What someone is like inside: their personality (kind, curious...).
son, sa, ses
his / her / its. It agrees with the thing owned, not the owner.