Past perfect

Ação que tinha acontecido antes de outra; past before the past.

Estrutura:

AFFIRMATIVE = SUBJECT + HAD + VERB(PART)
NEGATIVE = SUBJECT + HAD + NOT + VERB(PART)
INTERROGATIVE = HAD + SUBJECT + VERB(PART)

Exemplos:
 
    They had had pizza for dinner when I got home (Eles tinham tido pizza quando eu cheguei em casa)