Forming this tense we have to use two auxiliaries: Have and Been. Let's see
Affirmative
Subject + had been + Verb -ing + complement
- I had been working in Europe when I got pregnant
- She had been sleeping before he fell and broke his leg
- We had been singing the whole week since we were fired
Negative
Subject + had+ not+ been + Verb -ing + complement
- I had not (hadn't) been working in Europe when I got pregnant
- She had not (hadn't) been sleeping before he fell and broke his leg
- We had not (hadn't) been singing the whole week since we were fired
Interrogative
Auxiliar Have ( HAD) + Subject + Auxiliar Been+ Verb -ing + Complement
- Had I been working in Europe when I got pregnant ?
- Had She been sleeping before he fell and broke his leg?
- Had We been singing the whole week since we were fired?
Affirmative
Subject + had been + Verb -ing + complement
- I had been working in Europe when I got pregnant
- She had been sleeping before he fell and broke his leg
- We had been singing the whole week since we were fired
Negative
Subject + had+ not+ been + Verb -ing + complement
- I had not (hadn't) been working in Europe when I got pregnant
- She had not (hadn't) been sleeping before he fell and broke his leg
- We had not (hadn't) been singing the whole week since we were fired
Interrogative
Auxiliar Have ( HAD) + Subject + Auxiliar Been+ Verb -ing + Complement
- Had I been working in Europe when I got pregnant ?
- Had She been sleeping before he fell and broke his leg?
- Had We been singing the whole week since we were fired?