I'm sorry I don't have time to go to the supermarket with you.
→ I wish I had time to go to the supermarket with you.
We are thinking with pleasure about our camping trip to Cuc Phuong National Park.
→ We are looking forward to our camping trip to Cuc Phuong National Park.
In the past, Vietnamese people often had black teeth and wore hair buns.
→ In the past, Vietnamese people used to have black teeth and wear hair buns.
An started doing yoga at 6 o'clock.
→ An has been doing yoga since 6 o'clock.
Why don't we raise money for charity? (suggest)
→ I suggest that we raise money for charity. (Or: I suggest raising money for charity.)
This is the first time Alice tried Com Lang Vong in Viet Nam. (never)
→ Alice has never tried Com Lang Vong in Viet Nam before.
Although he went inside the Imperial Citadel, he didn't see the archaeological sites. (despite)
→ Despite going inside the Imperial Citadel, he didn't see the archaeological sites.
If you don't send her to the hospital, she may die. (Unless)
→ Unless you send her to the hospital, she may die. ("Unless" means "if not.")
you/Do/to/rubbish/sort/know/how/?
→ Do you know how to sort rubbish?
decided/We/visit/to/ have / Lenin Park/.
→ We decided to have a visit to Lenin Park. (Or: We decided to visit Lenin Park.)