Method of Salaah

Incorrect pronunciation in tashahhud

Q: I have one major problem during salaah and that is that I cannot pronounce in the tahiyyaat the last letter (n) of the word " as saliheen" especially during the first tashahhud. So I keep repeating it, until I manage to pronounce it. If I will recite it as "as salihee" without the last letter "n" would that be also valid and the meaning still correct? Or should I recite like "as salih" without "een" at the end, like the tanween we do not recite at end of ayaats?

Taking a breath after every Aayat

Q:

1. When reciting surahs in salaah, does one have to t​ake a breath after every verse or can they just pause slightly and go onto next verse.

2. What if they stop and take a breath on a part they should not and carry on reading. Like in Surah Fatiha, I sometimes take a breath just before 'ghair ril maghdoobi alaihim' even though there is no pause there. Is my Salah ok in both cases?