Plusquamperfekt: The Past-Before-the-Past

hatte/war + participle marks the earlier of two past events

This is exactly the Perfekt tense you already know — haben/sein plus a participle — except the auxiliary itself shifts into the simple past (hatte instead of habe, war instead of bin) to push the whole event one step further back in time. Telugu usually doesn't need a dedicated form for this at all: the past participle తిన్న (thinna, 'having eaten') already carries 'this happened first' built into its shape, so తిన్న తర్వాత ('after eating') needs no extra auxiliary layering the way German's hatte gegessen does. Reach for Plusquamperfekt specifically when a German sentence has two past events and you need to make the sequence explicit, especially after nachdem, bevor, and als — precisely the contexts where Telugu is content to let a bare participle clause do the same job.