1)We have read all the exercises  
2) My sister cleaned the room  
3) Masha has never been in America 
 4) My brother works at the school 
 5) The older sister is listening to music now, and my brother playing a computer game
 6)Tomorrow, my mother and I go to the museum
7) Yesterday, my grandfather was in the city
8) My mum was not at school yesterday.
9) My mother is sitting and watching TV now
 10) My sister is reading an interesting book

1.We have already read all the exercises.
2. My sister have cleaned all in the room.
3.Masha never been in America.
4.My brother works at school.
5.My older sister is listening music right now and my brother is playing the computer game.
6.Tomorrow I and my mom will go to the museum.
7.My grandfather was in the town.
8.Yesterday my mom wasn't at work.
9.Right now Mom is sitting and watching television.
10.My sister is reading interesting book.