The questions were very difficult. He solved them easily.
Although/ Though the questions were very difficult, he solved them easily. He solved them easily although/ though the questions were very difficult.
He was a great actor. He never played a leading role in a film.
Although/ Though he was a great actor, he never played a leading role in a film. He never played a leading role in a film although/ though he was a great actor
They spent a lot of money on the film. The film wasn't a big success.
Although/ Though they spent a lot of money on the film, the film wasn't a big success. The film wasn't a big success although/ though they spent a lot of money