Past Perfect Continuous

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Perfect tenses are used whenever we are talking about a point in time before another point in time.

Past Perfect Use for an action that happened in the past before another action. e.g. - I had already eaten breakfast when my brother arrived.

Present Perfect Use for an action that happened in the past before the present moment. e.g. - I have already eaten breakfast.

Future Perfect Use for an action that will happen in the future before another action. e.g. - I will have already eaten breakfast by the time my brothers arrives.