12.1
2. she was reading a newspaper
3. she was cleaning her flat
4. she was having a lunch
5. she was washing some clothes
6. she was watching television
12.2
1. Ann was writing a letter in her room
2. George was getting ready to go out
3. Carol and Dennis were having a dinner
4. Tom was making a phone call
12.3
1. The phone was ringing when I had a shower
2. It began to rain when I was walking home
3. We saw an accident when we were waiting for the bus
12.4
1. fell, was painting
2. was reading, heard
3. Was you watching
4. was waiting, arrived
5. wasn't driving, was happened (пассивный залог, но если вы ещё не проходили, напиши просто "happened")
6. broke, was doing, slipped
7. took, wasn't looking
8. didn't go, was raining
9. did you do
10. saw, was wearing