17. A. orange 18. A. explain 19. A. study 20. A. nervous 21. A. dinner 22. A. writer 23. A. August 24. A. behind 25. A. cooker 26. A. action 27. A. mountain 28. A. machine 29. A. villa 30. A. listen B. hippo B. shopping B. discuss B. visit B. candy B. supply B. seven B. colour B. travel B. because B. river B. healthy B. believe B. morning C. chicken C. lesson C. sister C. offer C. student C. question C. divide C. study C. machine C. happen C. control C. famous C. offer C. prepare D. expect D. enter D. friendly D. invent D. combine D. Monday D. painting D. hungry D. cupboard D. Sunday D. classmate D. paper D. picture D. promise