1. I started working at eight and I was still working at six in the evening, when you called. (been)
When you called, ten hours.

2. We often went to the seaside with our grandparents as children. (would)
Our grandparents to the seaside as children.

3. It's about seven years now since Laura started to learn Russian. (learning)
Laura seven years.

4. Being with the older children soon stopped being frightening when I went to secondary school. (used)
Secondary school was frightening, but I with the older children.

5. Every night for the past week I have had the same dream. (having)
I for a week now.

6. I always disliked karate lessons but now I'm starting to enjoy them. (used)
I karate lessons, but now I'm starting to.