present simple - past continious - past perfect.
1. It ___ when we ___ home. C) was snowing, left
A) was snowing, were leaving
B) snowed, left
C) was snowing, left
2. While my friend............, I ...........the birds. C) was fishing, was watching.
A) had fished, was watching
B) fished, watched
C) was fishing, was watching.