... is smoke from factory chimneys harmful to our environment? 38. What does “this” in ( However, it is not possible to do this) mean? 39. What do car exhaust fumes contain? 40. What sources cause ... safeguarding and preservation (27) natural resources, so that (28) can continued to be used and enjoyed. In the past, most people believed up. Today, we know that this is not true. An important ... without saying a word 48. The cupboard was too expensive (for me) to buy 49. Joan Brady wrote this novel 50. Peter said: “How about going to the booking office yourself?” Caâu 7: (20 ñieåm)...