@Your confidant

I'm a native English speaker. An 'e' at the end of a word changes the vowel sound. We called it magic 'e' in school. 

With magic e: like, life, combine

Without magic e: kid, rid, profit

It works for other vowels too e.g:

With magic e: rote, fate, state 

Without magic e: rot, fat, stat

There is no hack, and there is no ''perfect'' english. Really, how can you be a teacher and forget about each CITY from city language variation?

There is no 'losing' an accent.

Unless you become a voice actor (such as myself), then you need to follow strict rules as 'pronunciation' goes.

But, please study linguistics, phonetics, variation, syntax, and mainly History.

You CAN NOT be fluent in 3 months and be good at the 4 skills.

You can, nevertheless communicate in a good way inside 3 months if you dedicate yourself into it.

Gosh.