When to use Simple Past or Past perfect for two past in English?

Question

Suppose today I received call for an Interview from XYZ Company in which I was interviewed 2 years back. Now I want to tell them about this how would I say?

a) Two years back I had gone there for an interview but did not get selected.

b) Two years back I went there for an interview but did not get selected.

I know it is all about simple past and past perfect tense. In above sentences there are two pasts one is going there for the Interview and not getting selected in the interview. Both of my answers have same meaning. Hence which tense is proper to use in my answer?

Answer 1

Use of perfects depends on the context.

If the text before this sentence is cast in the past tense and talks about some past situation which occurred after that interview, you need the perfect to locate the interview prior to that situation.

I joined my present company in early 2015. I had gone to an interview with XYZ the previous fall, but was not selected.

But if you are talking about your present situation, a simple past is preferred:

I am delighted to appear for an interview with your company. I have always admired XYZ as an innovative leader in my field; in fact, I went to an interview there two years ago, but was not selected.

The golden rule is FumbleFingers' Perfect Truism:

Don't use Past Perfect unless you really have to.

Answer 2

To this native US speaker, the second ("Two years back I went there") sounds natural and the first ("Two years back I had gone there") does not. The reason is that you are simply telling about two events that happened in the past, not placing them in relation to each other.

Think of it this way: you could break the sentence into two separate, simpler ones.

I went there.
I did not get selected.

and they would both still be meaningful and correct. You wouldn't say "I had gone there." as a standalone sentence in this case, which is a good hint that it's probably not right for the longer sentence either.

We use the perfect to specify that one event in the past happened before another event in the past, so using the perfect "I had gone there" makes it sound like you had already been there before they did not select you. As StoneyB points out, the perfect could be useful if you are talking about two separate events in the past - for example, yesterday I went there and got selected, but two years ago I had gone there and did not get selected - but in this case it doesn't sound like that's what you mean.