Помогите нужно расставить артикли!

Помогите нужно расставить артикли! 1. Mary's two children are at … college… boy is at … . medical school. and… girl is at… teaching trainingcollege. 2. Не sat down at… piano and played… piece that he had played in … morning. 3. But I won't have … cup of tea. I'll have … coffee.