Question

1). When the old man got up/had got up to speak, everyone applauded. 2). They were chatting as if they knew/had known each other all their lives. 3). I was taking/took an umbrella because it was raining/rained. 4). It was a cold winter tonight. It was snowing/snowed hard and I was wanting/wanted to get back home quickly.

Answer 1

Had got up
had known
took
was raining
was snowing
was waiting

Answer 2

1. Both "got up" and "had got up" are correct, but "had got up" implies that the old man got up before something else happened, while "got up" simply indicates that he stood up to speak.
2. "Knew" implies that they had known each other for a while, while "had known" implies that they had known each other even longer. Either tense could be used depending on the context.
3. "Was raining" indicates that the rain was ongoing when the speaker took the umbrella, while "rained" indicates that it was a brief occurrence. Both "taking" and "took" are correct depending on the context.
4. "Snowing" indicates ongoing snow, while "snowed" indicates a brief snowfall. "Wanting" suggests ongoing desire, while "wanted" suggests a past desire that has since been fulfilled or abandoned.