C2 adjective /ˌpluːˈpɜːrfɪkt/
pluperfect
过去完成时
Meaning
a verb tense expressing an action completed before another past action
Example
By the time she arrived, he had finished his homework, showing the pluperfect tense.
在她到达时,他已经完成了作业,展示了过去完成时。