По . 1. i _ letters right now. 2. i _ 5 letters so far. 3. i _ 5 letters yesterday. 4. i _ 5 letters by the end of the week. 5. i _ letters when the phone rang. 6. i _ letters every day. 7. i _ 5 letters tomorrow. 8. this time tomorrow i _ letters. 9. i_ letters before she came home.