1. Although prescription medicine can help cure a disease, it can hurt you if you take too much.
("Although" usually appears at the beginning of a sentence.)
2. Her cell phone doesn't work although it's new.
3. Although it tastes good, candy is really bad for your teeth and for your body.
4. He's not as healthy as he looks although he works out a lot and he's very strong.
5. Although he's very careful when riding a motorcycle, he still takes many risks by not wearing a helmet.
6. I like to work on my website although looking at images and text on a computer screen for too long makes me tired.