Past perfect continuous tense – English editing.

This tense is formed by had been followed by the Present Participle:
She had been writing.
Uses:
To refer to an action that continued over a period in the past:
He had been studying hard for some hours.
To refer to a continuing action in the past contrasted with a single completed action in the past:
Timothy Harris, 33, had been working in Ilfracombe, Devon, when he met his girlfriend Faye Whitehead.
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