I understand that 'e' can be pronounced either as an 'eu' (example: je, le, etc.), open e, or closed e.
No one of the above sounds fits to how I hear that the word "rendre" is pronounced, where 'e' is pronounced more like an 'a'. Why is that? When does this happen?
Also, I think that there is also different pronounciation of the 'e' between:
Indeed, rendre uses a nasal vowel. There are many, many questions and resources online to explain and demonstrate French's 4 nasal vowels (or 3 depending on dialect).
To determine if a vowel is nasal:
☑ Is it before a nasal consonant? (n, m, ng)
☑ Is that nasal consonant silent?
If so, you have a nasal vowel.
A nasal consonant is pronounced if it has a vowel after it.
Test your knowledge. Do these words contain nasal vowels?
plan
Nasal vowel an
scène
No nasal vowel
pomme
No nasal vowel. Even though the first m technically doesn't have a vowel after it, that's just spelling, and what's important is that you can hear an m sound.
ensuite
Nasal vowel en
unique
No nasal vowel
rendre
Nasal vowel en
Exceptions are very few. e.g. in fan, a loanword from English, the n is heard and so there is no nasal vowel even though it looks like the same case as plan. Also see jlliagre's excellent finds (first one is a nasal vowel + a pronounced n, second one begins with the sound of English "pen").
Phonetically "en" in "rendre" is a nasal vowel, i.e. air is expired both by the nose and the mouth.
They may be written en em an am aen aon as in le vent, décembre, blanc, la chambre, Caen, un paon.
The word "prenons" is composed of the 2 phonetic syllables "pre" and "nons" (and not "pren" and "ons").
The termination "ent" of verbs is systematically mute.
Then the only remaining ambiguity is the pronunciation of the first syllable of "prennent" because of the 2 "n". The syllabic hyphenation is in this case different from phonetic break. But in French, all words ending by "enne" are pronounced as a simple oral vowel, like "pen" in English.
