"I am eating my sandwich."
Translation:Je mange mon sandwich.
Can someone explain what is the difference between "mon" and "ma", I wrote Je mange ma sandwich, and it was wrong.
"Mon" and "ma" both meant "my," but mon is used for masculine nouns: mon sandwich, mon stylo, mon sac, etc. Ma is used with feminine nouns like: ma lettre, ma maison, ma voiture. Unlike English, the agreement comes with the noun not the person possessing it. Therefore it is always masculine even if a woman owns the sandwich. Her sandwich = son sandwich.
Check out the tips and notes here: https://www.duolingo.com/skill/fr/Possessives/tips-and-notes
un sandwich is masculine in French. mon/ma/mes are called possessive adjectives, and adjectives have to agree in gender and number in French. Since sandwich is masculine singular, you have to use mon (also masculine singular)
Can someone please explain when we will use "mes". I understand "ma" is for féminin nouns and mon for masculin nouns. But "mes"??
Certainly! "Mes" is for plural nouns whether they are feminine or masculine.
my sandwiches = mes sandwichs
my chickens = mes poules
my books = mes livres
Other plural possessive adjectives: tes, ses, nos, vos, leurs