II. When
1. I will go ha noi TORMORROW.
2. They played soccer YESTERDAY. 
3. She planted trees LAST YEAR.
4. My family visited ha long bay LAST SUMMER VACATION.
5. My brother left Ho chi minh to Ha Noi IN 1993
6. I often have lunch AT 12
7. My friends and i will visit Sam Son beach NEXT MONTH.
8. He brought maize into Viet Nam IN 1838
9. Columbus discovered America IN 1942 
10. They could play guitar LAST YEAR
11. My sister could write WHEN SHE WAS A YEAR OLD.
12. Susan's sister cut the flowers YESTERDAY. 
13. Long wrote to me LAST NIGHT.
14. My class will have an English test NEXT WEEK.
15. Mark Twain died IN 1465