Past perfect

 Afirmative.

Singular: I Had+Participle past or verb ed/He Had +Participle past or verb ed/She                                  Had+Participle past or verb ed/It Had +Participle past or verb ed

Plural: We Had+Participle past or verb ed/You Had+Participle past or verb ed/They                               Had+Participle past or verb ed

Negative.

Singular: I Had not+Participle past or verb ed/She Had not+Participle past or verb                               ed/It Had not+Participle past or verb ed/

                 I Had´t+Participle past or verb ed/You Had´t+Participle past or verb ed/He                               Had´t+Participle past or verb ed/She Had´t+Participle past or verb ed/It                                     Had´t+Participle past or verb ed

Interrogative.

Singular: Had I+Participle past or verb ed/Had He+Participle past or verb ed/Had                                 She+Participle past or verb ed/Had It+Participle past or verb ed       

Plural:    Had We+Participle past or verb ed/Had You+Participle past or verb ed/Had                            They+Participle past or verb ed 

Use.

Used to talk about an action that accurred before another action in the past.

Used to talk about actions completed before a specifc point in the past.

To form the negative."not" is added after the verb "to have" 

Irregular verbs

Yes in the past perfect used irregular verbs