Помогите решить третье и 4

задачка 3
1) I didnt play the piano yesterday
2) Well go to the sircus tomorrow
3) Nicks a real friend
4) This company exports building materials into the Ukraine
Задачу 4 не поняла, сори

3. 1 did not play
    2 will go
    3 is
     4 exports
4. 1 is
    2 was
    3 will be
    4 are being