I've learnt that
- Entre is used when there is question of two;
- Parmi is used with a collection of objects and always demands after it a plural noun or a collective noun.
I recall our professor said that we can think about the English respective words 'between' and 'among'.
Apparently, I must be missing several things because I have noticed several times native speakers using entre whereas the logical choice would be parmi.
What are the differences between entre et parmi?
When can't we use the former in the place of the latter and vice versa?
When can we interchangeably use one in the place of other?
I am quite sure that entre is used more in colloquial speech even in cases that require parmi. The latter is considered more formal. Is my conjecture correct?
Can one say that there is one-to-one correspondance between 'entre and between' and 'parmi and among'?