Compared with last year, our pay _____ about ¥500 every month.
I hear that Tom will be back _______ a month.
Doing sports is good for your health, _______ ?
––Would you mind _______ the music? Your grandpa is sleeping.––Sorry. I’ll do it right away.
––_______ have you been a volunteer? ––Since three years ago.
He has been collecting coins _______ he was seven years old.