1. They have been turning the TV and the video on and off all evening
2. They have been using dad`s camera and they have been taking a lot of pictures.
3. They have been playing Kate`s cassette recorder really loudly.
4. They have been pulling the vacuum cleaner up and down the stairs.
5. They have been running backwards and forwards to the fridge non-stop.
6. They have been making pancakes for the last two hours.