Ответ:

3 had been teaching (Past Perfect Continuous), broke (Past Simple)

4 helps (Present Simple), have been doing (Present Perfect Continuous), have already washed (Present Perfect), have dusted (Present Perfect), are cooking (Present Continuous)

5 had been writing (Past Perfect Continuous), hadn't eaten (Past Perfect) (согласование времен - слова автора в прошедшем времени)

Объяснение:

Ответ:

3. he had been teaching when the war broke out 4. always helps. They have been doing .... have already washed .... and dusted. Now they are cooking dinner. 5. had been writing and had not eaten