1. Vinh usually stays up late to watch soccer matches. He knows it isn't good for his health. (although)
=> Although Vinh knows staying up late is not good for his health, he usually stays up late
2. I'm not interested in soap operas. They are often long and boring. (because)
=> Because soap operas are often long and boring so I am not interested in them
3. Lan went to bed before the game show ended. She was tired and sleepy. (so)
=>  She was tired and sleepy so Lan went to bed before the game show ended.