He does not need to call us every hour, because we will send him a fax. 2. He should not call us every hour, because we are very busy. 3. He can not call us every hour, because he does not have a mobile phone. 4. Maybe he calls us every hour, but our phone is always busy. 5. Do I need to call you every hour? 6 He had to call us every hour, but he left his mobile phone at home. 7. He will have to call us every hour as soon as he meets his English colleagues. 8. He can call us every hour when he has a mobile phone. 9. She does not need to buy this dictionary, because we will give it to her. 10. She should not buy this dictionary, because there are few words in it. She can not buy this dictionary, because she can not find it in stores. 12. Perhaps she will buy this dictionary bookstore near the university. 13. Should I buy this dictionary? 14. She should have bought the dictionary yesterday for me, but she did not buy it, because she did not have time. 15. She will have to buy this dictionary tomorrow for me, because she will be free. 16. She will be able to buy this dictionary for