4. When I finished school my elder sister (had been a teacher for two years).
5. We (had already made all the arrangements) when we learned that he
wouldn't come.
(C) 1. I knew her immediately because my brother (had described her to me
very well). 2. The militiaman stopped her because she (had crossed the street
in the wrong place). 3. I was not hungry because I (had had lunch just an
hour before). 4. Nobody knew when he came in because he (had entered the house
through the back door). 5. I thought he knew English well because he
(had lived in England for some years). 6. It happened to him because he
(had always been too sure of himself).
(D) 1. As soon as they (had taken a decision) they could discuss less
important questions. 2. After we (had made a fire) it became warm. 3. When I
(had thrown out all the old newspapers and magazines) I could arrange my new
books nicely on the shelf. 4. After he (had paid the money for the plane
tickets) he had very little left in his pockets. 5. I met her soon after
I (had learnt the news). 6. When he (had finished his work) he went to bed.