PAST PERFECT PROGRESSIVE
Past Perfect Progressive is used for an action that had been happening before another action in the past happened.
S + HAD + BEEN + V ing ( affirmative )
1. Mr. Heru had been teaching for an hour in my class before he went home.
2. Mr. Lukman had been reading a newspaper in the library before he taught in my class yesterday
3. Mr. Rina had been repairing for an hour before you met me.
S + HAD + NOT + BEEN + V ing (Negative )
1. Mr. Lina had not been reading a magazine in the library before she taught in your class yesterday.
2. Lina had not been helping me before she went to her office yesterday.
3. Rini had not been watching TV before she visited you yesterday.
HAD + S + BEEN + V ing ? ( Interrogative )
1. Had Lina been helping her mother before she went to office?
2. Had Rini been watching TV before she visited you yesterday?
3. Had Mrs. Lina been reading a newspaper before she taught in your class?