+0
I simply can't seem to understand the difference between these two tenses. I mean i know the difference but when it comes to speaking i always get confused in which one to use. Like in the example below i dont know which one is correct and what is the difference in their meaning:

i had been a studious student during my school days, and by the end end of my college days i had transformed into a brat.

i had been a studious student during my school days, and by the end end of my college days i transformed into a brat.

basically i want to say that the person was very studious in his college days but became a total brat in his college days. which of the above statements convey(another question, convey or conveys?) what i want to convey?

can someone explain me some sort of trick to remember when to use past and when to use past perfect tense?
+0
As Mr Micawber wrote, " past perfect is seldom needed and it is a misallocation of learners' time to worry them overmuch with it.

I'll give one example of a sentence it in which it is necessary:

The had left when I arrived.

In this example, the past perfect shows that the leaving happened before the arriving. If the sentence had been, "They left when I arrived", then the leaving would have happened at the same time as, or shortly after, the arriving.

However, that is the sort of example teachers and course books produce when they are trying to teach the past perfect. It's correct, but comparatively uncommon.We are just as likely, to say, just as correctly, "They left before I arrived". It is possible, to use past pefect "they had left" in that last sentence, but not necessary.
Comments  
There is no call for past perfect in any of those sentences, and there is seldom any call for it in the spoken language. It is almost completely used in formal, carefully written English in two specific cases: to indicate the earlier of two past events when the order of their occurrence is not otherwise clear, and to emphasize that same relationship of 2 past events.
Students: Are you brave enough to let our tutors analyse your pronunciation?
@Mister Micawber

Isn't it natural to say 'had been - transformed', though?

With other words:
You transformed into a brat, but before you had always been a studious student.

LS
What I am saying is that past perfect is seldom needed and it is a misallocation of learners' time to worry them overmuch with it.
ok. So while speaking i should explain the order of the events by using while, before, after etc?. Because i always get confused as when to use the past tense and when past perfect. It has been bugging me for quite a while now. Could you please explain me the difference in meaning they bring with the help of some examples?i would be extremely thankful to you.
Teachers: We supply a list of EFL job vacancies
 fivejedjon's reply was promoted to an answer.