It is true that we have changed the pronunciation of most of the English words but fact of the matter is this is not our first language. There are many countries where English is being spoken and taught but they can't properly understand even the most educated people. As far as the accent is concerned, Pakistanis are way too good then even Indians although they are more educated but face problems in speaking fluent English along with proper pronunciation. Most of the English words are being generalised and are quite common in Pakistan, so if someone says any word different than the generalized word, people will have problems to understand. Even we make mistakes in speaking Urdu let alone English.
