The students were writing their exam.

Here are the completed sentences using the past continuous form of the verbs:

1. The students were writing their exam.
2. The child was crying for the toy.
3. The dogs were barking loudly.
4. The wind was blowing fiercely.
5. The birds were singing sweetly.
6. The farmers were cutting trees in the field.
7. He was driving fast across the bridge.
8. Last night at 6 PM, I was eating dinner.
9. At midnight, we were still driving through the forest.
10. Yesterday at this time, I was sitting at my desk at work.