Which one is correct?
1.The Department had been sent all the relevant documents of pension in 2006.
2.The Department has been sent all the relevant documents of pension in 2006.
#1 is correct, because you are referencing the time before 2006. If you have no reference point (aka present) then you would use has. (“The Department has been sent all the relevant documents of pension.” – that means as of now.)
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#2 is not correct because you have mentioned a clear past date. #1 is odd when standing alone; there is no call for past perfect. This is the expected:
The Department was sent all the relevant pension documents in 2006.
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