1.

I had to catch a train, but it took me four hours to get to the station.

, my train had already left.

2.

I saw two men who looked as if they were trying to steal a car. So I called the police, but they arrived very late.

, the two men had disappeared.

3.

I wanted to go to the movies after finishing my work. But I finished my work much later than expected.

, it was too late to go to the movies.