PAST PERFECT CONTINUOUS TENSE

Definition :

Action in progress immediately before, up to, until another time or action in the past

Pattern :

+ S + Had + Been + VI(ing) + O

S + Had + Not + Been + VI(ing) + O

? Had + S + Been + VI(ing) + O

Examples :

+ They had been singing, when we studied dancing

- They had not been singing, when we studied dancing

? Had they been singing when we studied dancing?

+ I had been writing the lesson when Rudi met me

- I had been writing the lesson when Rudi met me

? Had I been writing the lesson when Rudi met me?