Вставьте модальные глаголы саn , may , must, need: 1. shall i write a letter to him? -no,you not,it's not necessary. 2. i offer you something to drink? 3. everything is clear and you not go into detail now. 4. he not drink alcohol when he drives. 5. don't worry! i change a light bulb. 6. by the end of the week i have finished writing my book. 7. she not call the doctor again unless she feels worse. 8. peter return the book to the library. we all want to read it. 9. why not you understand it? it is so easy. 10. we do the exercise at once? - yes, you do it right now.