22. A) Their average life span was less than 50

　　23. C) learn to use new technology.

　　24. D) When all people become wealthier

　　25. C) Control environment

　　26. B) To alert teenagers to the dangers of reckless driving

　　27. A) Road accidents

　　28. C) It has accomplished its objective

　　29. B) Customers may be misled by the smells

　　30. C) Supportive

　　31. A) The flower scent stimulated people’s desire to buy.

　　32. C) A passenger train collided with a goods train

　　33. D) The exact casualty figures are not yet available

　　34. A) There was a bomb scare

　　35. D) Drive with special care

　　36. tongue

　　37. official

　　38. administration

　　39. commerce

　　40. spread

　　41. disadvantaged

　　42. competence

　　43. investigate

　　44. come to understand how it is used as a symbol of both individual identity and social connection

　　45. infants born into English-speaking communities acquire their language before they learn to use forks and knives

　　46. You are encouraged to develop your own individual responses to various practical and theoretical issues