7. (you/finish) your homework yet ?
10. it (snow) when we(leave) the library.
11.- i usually
(listen) to the news in the car.
12. my cousin is a writer. he
(write) three novels.
13.- be careful! the baby
(put) those keys in
his mouth
14.- when
(barack obama / become)
president of the usa?
15.- my students
(not listen) when i gave the instructions.​

Объяснение:

7) Did you finish your homework yet?

10) It was snow when we left library.

11) I usually listen to the news in the car.

12) My cousin is a writer. He wrote there novels.

13) Be careful! The baby put those words in his mouth.

14) When was Barack Obama become president of the USA?

15) My students doesn't listen when I gave the instructions.