Possessive Adjectives

The possessive adjective defines the noun with an idea of belonging.

SINGULARPLURAL
French
Masculine
French
Feminine
English
 
French
Masc/Fem
English
 
monma/mon+vowel/mute hmymesmy
tonta/ton+vowel/mute hyourtesyour
sonsa/son+vowel/mute hhis/her/its/one'sseshis/her/its/one's
notrenotreournosour
votrevotreyourvosyour
leurleurtheirleurstheir

1 - The possessive adjective agrees in gender and number with the noun, not with the owner

It is Paul's turn now. It is his turn.
It is Sophie's turn now. It is her turn.
It is the dog's turn now. It is its turn.

C'est le tour de Paul maintenant. C'est son tour.
C'est le tour de Sophie maintenant. C'est son tour.
C'est le tour du chien maintenant. C'est son tour.

Note that the adjective used in English is 'his' or 'her' depending on the gender of the owner, male female or neutral.
But in French, the adjective depends on the gender of the noun, whether the noun is masculine or feminine.
As the word 'tour' is masculine (un tour), the adjective that should be used is the masculine form 'son' no matter the gender of the owner.

2 - When followed by a vowel or a mute 'h', the feminine singular pronoun ma, ta, sa becomes mon, ton, son.
This simply avoids to have two vowel sounds one after another, which would be uncomfortable to listen to.
By using mon, ton, son, this allows to link the pronoun with the following vowel by means of a consonant, which sounds much nicer when pronunced.
mon habitude and not ma habitude, although we say une habitude.
mon intention, not ma intention, although we say une intention.

-Where is my coat? Où est mon manteau?
-I don't know, have a look in your cupboard. Je ne sais pas, regarde dans ton armoire
Note that you should say 'ton armoire' and not 'ta armoire', although 'armoire' is a feminine word - 'une armoire'.

I live close to my university.
J'habite près de mon université
Note that you should say 'mon université' and not 'ma université', although 'université' is a feminine word - 'une université'.

It was Paul's idea. It was his idea.
C'était l'idée de Paul. C'était son idée.
It was Sophie's idea. It was her idea.
C'était l'idée de Sophie. C'était son idée.
You should say son idée, even though idée is a feminine word - une idée.
As explained earlier you can also see that the possessive adjective is not dependant on the gender of the owner.