The past perfect simple tense is used to go further back in time when we are already talking about the past. It can make it clear that something had already happened at the time we are talking about.

Past Perfect Simple Timeline

                       

We form the Past ?Perfect Simple by using the auxilliary verb have in the Past Simple >HAD<and the -ed form of the regular verbs (the past participle)

 Irregular verb forms have to be learned:

( been/ gone/ written/ eaten/ etc. )

http://www.ego4u.com/en/cram-up/grammar/past-perfect-simple/exercises
http://www.englisch-hilfen.de/en/exercises/tenses/past_perfect_simple_past.htm
 
 

  Past Perfect / Past Simple

 
http://www.englisch-hilfen.de/en/exercises/tenses/past_perfect_simple_past.htm

http://www.ego4u.com/en/cram-up/grammar/simpas-pasper/exercises