$\text{1. They HAVE just DECIDED to buy a new house.}$
$\text{2. "Gone with the Wind" is the most interesting film we HAVE SEEN recently.}$
$\text{3. DID you see Nam last Sunday?}$
$\text{- Oh, no I HAVEN'T SEEN him for many days now.}$
$\text{4. Since when you LEARNT/LEARNED E?}$
$\text{- I LEANT/LEARNED it since I AM a girl of twelve}$
$\text{5. HAVE you ever BEEN to HCM city?}$
$\text{- No, I HAVEN'T BEEN there yet, but my parents HAVE BEEN there twice this year.}$
$\text{6. They HAVE DONE nothing since they GOT up}$
$\text{7. My brother JOINED the army when he WAS 18}$
$\text{- He HAS SERVED in the army for 3 years and then WENT to university}$
$\text{8. How long you LIVED in this town?}$
$\text{- I LIVED in this town for 10 years.}$
$\text{9. My sister FINISHED school in 1997 and was a student at the National University since then.}$
$\text{My parents HAVE GONE out. They'll be back soon.}$