Here's a breakdown:
"Quel" is used before masculine singular nouns:
* Quel livre veux-tu lire? (What book do you want to read?)
* Quel jour est-ce aujourd'hui? (What day is it today?)
"Quelle" is used before feminine singular nouns:
* Quelle couleur préfères-tu? (What color do you prefer?)
* Quelle heure est-il? (What time is it?)
"Quels" is used before masculine plural nouns:
* Quels fruits aimes-tu? (What fruits do you like?)
* Quels livres as-tu lu? (What books have you read?)
"Quelles" is used before feminine plural nouns:
* Quelles fleurs sont les plus belles? (Which flowers are the most beautiful?)
* Quelles chansons écoutes-tu? (What songs do you listen to?)
Examples of "quel" and "quelle" in questions:
* Quelle est ta couleur préférée? (What is your favorite color?)
* Quel est ton nom? (What is your name?)
* Quels sont tes passe-temps? (What are your hobbies?)
* Quelles sont tes envies pour ce soir? (What are your plans for tonight?)
Important Note: "Quel" and "quelle" can also be used in exclamations to express surprise or admiration:
* Quel beau jardin! (What a beautiful garden!)
* Quelle magnifique robe! (What a beautiful dress!)
By understanding the basic rules and practicing, you'll be able to use "quel" and "quelle" confidently in your French conversations.