Модуль (Module) 5c № 2. ГДЗ Английский язык Spotlight 10 класс Афанасьева. Помогите ответить про время.

Read sentences 1-7. What are the tenses in bold?
 
1     I was watching the parade when I saw an old
friend in the crowd.
2     He arrived safely in Egypt yesterday.
3     I was writing postcards while John was
sunbathing on the balcony yesterday afternoon.
4     I had just finished packing when my taxi
arrived.
5     The sun was shining and the birds were
singing in the trees.
6     He had been driving for three hours before he
reached his destination.
7     When we got off the plane, we waited for our
luggage.
 
Which tense:
a describes two actions which happened one after the other in the past?
b describes the setting for events?
c describes an action which happened at a definite past time?
d describes an action in progress interrupted by another past action?
e describes an action which happened before another past action?
f describes two actions in progress at the same time?
g emphasises the duration of an action which started and finished in the past before another past action?