B.
1. Because she had a toothache.
2. He bough at the bookstore.
3. She met her friend at the supermarket.
4. I visited the countryside.
5. We were at home.
C.
1. Linh and her parents saw many types of fish at Tri Nguyen Aquarium.
2. Liz and her parents went to visit Nha Trang two months ago.
3. We were in Ha Noi with our friends last week.
4. What did you do two days ago?
5. Was she in grade 6 last year?
6. I did not stay at home yesterday.
7. How does he go to work every day?
8. How did she travel to school yesterday?
9. What time we will meet Mai tomorrow?
10. I enjoy watching television in my free time.
11. Ba enjoys reading picture books.
12. Nga is interested in listening to English songs.
