III/ 1. didn't do/was/does 2. felt/went/is 3. waters/forgot 4. will you see 5. did you come/had
6. brushes/are 7. do you have/have/had 8. was/didn't have IV/ 1. We were quite tired because we worked very hard in the garden. 2. Nam went to bed early because he was tired. 3. Lan is very busy because she is having her final examination. 4. Ba felt worried because he had a serious toothache. 5. Mai had a nice gift because she studied hard this school year. 6. We had to start very early this morning because we didn't want to miss the bus. 7. Tam is sad because she misses her parents. 8. The machine doesn't work because there is no electricity. 9. Hoa brushes her teeth regularly because she doesn't want to have cavities in her teeth. 10. We go to Nha Trang this summer because we want to visit Tri Nguyen Aquarium.
