13.
a. How long have you been cooking the chicken in the oven? I've been cooking it for about twenty minutes.
b. How long has Carl Schmidt been playing football for Brazil? He's been playing for Brazil since the start of the season.
c. How long has he been cleaning his motorbike? He's been cleaning it for two hours.
d. How long have you been waiting to see the doctor? I've been waiting since nine o'clock.
e. How long has your sister been living in Florida? She's been living there for over a year.
14.
a. Do you realize I've been waiting here from two o'clock!
b. She's been living in Spain for six months.
c. He's been wearing contact lenses for over at least five years.
d. My father has been working for the same company since 1994.
e. The have been running the lottery in the UK for many years.
f. I've been collecting stamps since I was seven.