2. They/sent/these postcards yesterday.
S V O
3. We/should brush/our teeth twice a day.
S V O
4. I/saw/my old form teacher last month.
S V O
5. He/is writting/a letter right now.
S V O
6. The cat/catches/the mouse in the kitchen.
S V O
chúc bạn học tốt!!!!!