THE PAST PERFECT CONTINUOUS TENSE

a. Use:

1- The Past Perfect Continuous tense is used to refer to a continuous, ongoing action in the past which was interrupted by a second action in Simple Past. What is important is the duration of the action expressed through Past Perfect Continuous.

--> I had been waiting for two months by the time I received the reply.
--> He had been thinking about his friends shortly before they called.

In the preceding examples, the verbs had been waiting and had been thinking are in the Past Perfect Continuous tense, and the verbs received and called are in the Simple Past. The use of the Past Perfect Continuous tense indicates that the actions of waiting and thinking were continuous, and were interrupted by the actions expressed in the Simple Past.

2- Past perfect progressive tense lets you show that two actions took place in the past, one an ongoing action and the other a one-time action, and that the ongoing action preceded the one-time action.

--> Police had been tracking him for years and finally caught him.

The tracking went on for some time in the past. The catching was a one-time action that also occurred in the past. Furthermore, the tracking preceded the catching. --> Jones, who had been running, arrived out of breath. The running went on for some time in the past. The arriving was a one-time action that also occurred in the past. Furthermore, the running preceded the arriving. b. Formation: The Past Perfect Continuous tense is formed from the Past Perfect of the auxiliary to be, followed by the present participle of the verb. For example, the Past Perfect Continuous tense of the verb to work is conjugated as follows: I had been working you had been working he had been working she had been working it had been working we had been working they had been working The auxiliary had is often contracted to 'd in spoken English. c. Questions and negative statements: As is the case with other English tenses, questions and negative statements in the Past Perfect Continuous tense are formed using the first auxiliary. Questions are formed by placing the first auxiliary before the subject. For example: Affirmative Statement Question   I had been working.   Had I been working?   They had been working.   Had they been working? Negative statements are formed by placing the word not after the first auxiliary. For example: Affirmative Statement Negative Statement   I had been working.   I had not been working.   They had been working.   They had not been working. Negative questions are formed by placing the first auxiliary before the subject, and the word not after the subject. However, when contractions are used, the contracted form of not follows immediately after the first auxiliary. For example: Without Contractions With Contractions   Had I not been working?   Hadn't I been working?   Had they not been working?   Hadn't they been working?