Eita ke simple to compound Kore dae

Here are the simple sentences converted to compound sentences:

15. Simple: The water being very cold, I could not drink it. Compound: The water was very cold, so I could not drink it.
16. Simple: The lunch being over, we left the hotel. Compound: The lunch was over, so we left the hotel.
17. Simple: The sun having set, we returned home. Compound: The sun had set, so we returned home.