пожалуйста приведите примера на союзы:but,because,and,that's why,firstly,secondly,when,while.Заранее спасибо!

I'm quite smart but I don't understand it. I'm leaving because i have to go to school. This thing is red and blue. That's an amazing movie! Why do i have to do it? Firstly, you are late, secondly, it's too late to go anywhere. When i was young i liked swimming. My mum was watching a TV, when the phone rang.