.1.-open the window.
-but i have opened the window.
2.i have seen the film.
3.he has opened the door.
4.they have cleaned the room.
what do you want? - i want some tea.
who is playing the drums ? - it is my little brother. he plays the drums very well.
when do you leave the house ? - at 8.30 in the morning.
what are you doing ? - i am doing my homework .
what are the boys singing at the moment ? -they are singing an old english song.// //