De vs en

Question

Are these competely interchangeable for specifying what something is made of or are there pronounciation rules that indicate which one is better for a particular word?

Answer

Bonjour Joakim !

I would say that "en" implies that this is the main (and often only) element the thing is made of, whereas "de" would imply that it's one of the elements composing the thing, but there must be more.
Colloquially, "en" is used more often than "de".

I hope that's helpful!
Bonnes Fêtes et à bientôt !

Answer

Could you add some clarification re: wedding bells, baseball cap, tennis racquet, door knob, golf club, soccer ball, soccer field, sunglasses, Christmas tree, water tank, bus stop, fire truck, etc.

By your lesson, these should all be “à” (what something is designed for), but in fact this whole genre is “de”.

Specifically, why is it “boîte à bijoux” and not “boîte de bijoux” ? Other than convention.

Clearly, these are not just a few exceptions, but an entire class of compound nouns (open form, noun+noun) that is not covered in the lesson.

Thank you.

Answer

Put in wrong place

Answer

In the "A special Monday" dictee for "chocolate eggs" au or en was required and de was not allowed. Why is that? The egg is entirely of chocolate. If you take away the chocolate you have nothing.

Answer