12. She was breathless. She (to run) all the way to the cabin. 13. I (to work) at this problem for an hour before I asked my father to help me. 14. They (to travel) for three months by the time they return. 15. She said the children (to play) since they went out. 16. Tim (to make) the same spelling mistakes since I started teaching him. 17. We (to correspond) since moved to this town. 18. How long she (to study) French before she left for Paris? 19. The child is so dirty. He (to play) in the wet sand since morning. 20. My eyes are aching. I (to read) the report for the whole afternoon. 21. By the time we finish the tenth form, we (to write) a lot of essays and summaries

please

14. They traveled for three months by the time they return. 15. She said the childern played since they went out. 16. Tim maked the same spelling mistakes since I started teaching him. 17. We corresponded since we moved to this town. 18. How long she studied French before she left for Paris? 19. The child is so dirty. He played in the wet sand since morning. 20. My eyes are aching. I readed the report for the whole afternoon. 21. By the time we finish the tenth form, we write a lot of essays and summaries.