I have never quite got how this kind of structures work. Things like chaîne Youtube, or appareil photo. Shouldn't they be chaîne de YouTube or appareil de photo? Or do YouTube and photo work like adjectives? Could you tell me how and when is it okay to employ this kind of structures and perhaps some other examples? PS: Sorry if you don't get my question. I'm more of a native Spanish speaker than I am an English one, and in Spanish these kind of things are just plain wrong, they work by placing de and the second noun. What I mean is this: if for example fighter jet becomes avion de chasse, shouldn't other noun pairs work like so in French?