Verified answer

(3)

A. since

B. for

C. since

D. since

E. for

F. since

(4)

a. I have sung in school choir here for 2 years.  Я пою 2 года в школьном хоре здесь.

b. He has been my teacher for three years.  Он был у меня учителем 3 года.

c. I have been washing graffiti since Monday.  Я отмываю граффити с понедельника.