Here are the completed sentences:
1. We didn't have much money, so we stayed at the cheapest hotel in the town.
2. This building is 250 meters high, but it's not the tallest in the city.
3. It was an awful day. It was the worst day of my life.
4. What is the most popular sport in your country?
5. I like the morning. For me it's the best part of the day.
6. Sarah always tells the truth. She's one of the most honest people I know.
7. A straight line is the shortest distance between two points.