Para ver las explicaciones vaya al capítulo

Elija since or for según corresponda
check or answer
He has been sleeping
six hours now.
I have not seen him
more than ten years.
They have been living here
summer 1999.
She has been studying
last spring.
He has read this book
the last six months.
You have blond hair
you were little.
The milk has been in the refrigerator (= refrigerador)
Your little sister has been an ice skater
three months.
The flowers in your garden have blossomed (= florecer)
seven months this year.
He has been writing this letter
six this morning.