I've learned English long time, but I have seen difficult thing for remembering.
At the same tim, with a letter when i 've been read this way, and another time also read another.
First case: ape, ache, explain, /ei/
Second case: at, taxi, anniversary, laboratory /e/
Third case: consonant /er/.
If someone have completly pronounce rules, please post here for every one and me. I'm expecting for your reply
Welcome to the forums.
What you need are the phonetic symbols. Try here: Phonetics - Cambridge Dictionaries Online