Basic American English Grammar - Lesson 9 ( The Past Perfect Tense )

The past perfect tense is used with two past actions. 

The verb in the past perfect shows the first past action.

I had seen that video before but I forgot when I saw it .

First verb: see; Second verb: Saw

The word order can be changed but it doesn't change the meaning:

I forgot that I had seen that movie.

note:  Americans don't use this tense properly.

see / saw / seen
......................

I had learned  - We had learned
You had learned  - You had learned
He had learned
She had learned -  They had learned
It had learned