31. The five-year-old child was tired after a long walk with his father in the mountains and asked his father for a __________. But his father was exhausted, too.
(A) piggyback
(B) hunchback
(C) feedback
(D) horseback

27. Across Europe, there are about 400 of the new energy plants that burn thousands of metric tons of household garbage and industrial waste round the clock and, all the while, ___________ the trash into heat and electricity. (A) converting (B) convert (C) converted (D) to convert

28. Many nations in Europe already have binding commitments to __________ their carbon dioxide emissions by 2012 under the international pact known as the Kyoto Protocol. (A) decreasing (B) increase (C) deducting (D) reduce

29. The eight ocelots were seized from the estate of a murdered cocaine trafficker, who apparently believed that any self-respecting drug lord should always have eight ocelots in his _________. (A) dominance (B) disposal (C) dominion (D) disposition

30. Robert Burns, who wrote over 300 songs in Scots, a northern dialect of English spoken by Scottish peasants, also collected Scottish folk songs for a(n) ____________ called the Scots Musical Museum. (A) anthology (B) anthropology (C) literature (D) autobiography

32. One year ago, he was ____________ by a spirit and from then on he acted and spoke strangely. However, the villagers who thought he was out of his mind at first were surprised to find him able to foretell the future. (A) obsessed (B) haunted (C) obliged (D) possessed

33. Exposure of children to abuse toward women by their partners fosters the development of emotional problems in the children. These children grow up ashamed of the situation at home, thinking it is a family secret, which _________ keeps them from seeking help. (A) in turn (B) all in all (C) by contrast (D) in return

34. There are puddles on the ground outside. It ____________ last night. (A) must have rained (B) has rained (C) should have rained (D) may rain

35. By ___________ satellite transmitters in migrating birds, scientists are able to track a number of them. Their results show that some species can fly thousands of miles nonstop on their migrations. (A) implanting (B) embedding (C) transplanting (D) incising

36. A woman was found dead at a ditch. Unfortunately, the scene at the ditch was contaminated by some of the first responders, limiting the amount of forensic evidence that could be retrieved. Furthermore, ____________ occurred, which made it very difficult for investigators to take fingerprints or any other kind of forensic evidence. (A) erosion (B) evolution (C) decomposition (D) rustiness

37. If someone goes bananas, it means that he becomes very ___________. (A) worried (B) angry (C) happy (D) frustrated