1. I wrote a letter last night. 2. They have completed the plan successfully. 3. I received a letter from my pen-friend. 4. We all believe that Jack is an honest boy. 5. You must hand in your exercise books after lesson. 6. The meeting will last two hours. 7. Some birds fly to the south in autumn. 8. My brothers are all university students. 9. Days are short and nights are long in winter. 10. Mrs Brown looks very healthy. 11. This report sounds interesting. 12. I have written three letters to my parents in this term. 13. We will make our school more beautiful. 14. We hear him reading English loudly every morning.