French language Q&A Forum

I'm confused when to use penser à and when to use penser de, and why you would say "la fille à laquelle je pense" instead of "la fille dont je pense" 

Hi, 

How does orange changes in plural?

According to the video tagged, orange doesnot change to plural, but in the quiz it marked my question wrong.

Pls suggest the right way.

"For pronunciation reasons, you will use en with masculine countries starting with a vowel" yet États-Unis is using aux. Is that only because it is plural?

Quelle est ton nationalite ou quelle est ta nationalite?

ton pour M et ta pour F. c'est correct