Phonetics:

1: O

When is alone in any word; ‘ O ‘  sounds like hindi alphabet  

For example:   Pot  sounds like   hindi    

But whenever ‘E’ or ‘A’  vowel comes after the alphabet ‘ O ‘,  the sound changes to  the  hindi alphabet  

for example:  Pote or Poat  will now sound as  

More examples:

With Only O                  With O and any other vowel

Bot                               Boat

Lot                                Loat

Hop                               Hope

Pop                                 Pope

Blot                               Bloat