Vowel Reduction in Russian

I’m still working on pushing along in Russian–following the New Penguin Russian Course and working with a local native speaker on a weekly basis and starting to meet with someone here at school who speaks it fairly fluently (as I’ve been told).

One of my lingering questions has concerned the ‘vowel reduction’ that takes place with о/а, е/и, and sometimes я. The NPRC tells me that in unstressed syllables, о is pronounced as а, and е is pronounced as и. Also, before the stress, я is also pronounced as и. However, both in the book and in my work with my tutor, only the о/а and я rules seem to be religiously followed; севодня, for example, is pronounced as “sye-vod-nya.”

What is the rule on е/и? Should севодня sound like сиводня, Санкт–Петербург sound like Санкт–Питирбург, and неделя sound like ниделя?

(Also, I’m feeling a bit frustrated and discouraged at the moment, though at the same time fascinated, even slightly obsessed. General words of encouragement would be appreciated. :))

Please forgive my spelling errors. Stupid genitive ево/его thing. :smack: