exactly when he acquired the use of The 52 of language is also obscure. No doubt it began very gradually Animals have a few cries that serve 53 signals. 54 even the highest apes have not been found able to pronounce words, 55_with the most intensive professional instruction. The superior brain of man is apparently 56 for the mastering of speech. When man became sufficiently intelligent, we must suppose that he 57 the number of cries for different purposes. It was a great day 58 he discovered that speech could be used for narrative. There are those who think that 59 picture language preceded oral language. A man 60 a picture on the wall of his cave to show 61 direction he had gone, or 62 prey he hoped to catch. Probably picture language and oral language developed side by side I am inclined to think that language the most important single factor in the development of man Two important stages came not 64 before the dawn of written history The first was the domestication of animals; the second was agriculture. Agriculture 65 in human progress to which subsequently there was nothing comparable until our own machine age. Agriculture made possible an immense increase in the number of the human species in the regions where it could be successfully practiced These were, at first, only those in which nature fertilized the soil after each harvest. Agriculture met with violent resistance from the pastoral nomads, but the agricultural way of life prevailed in the end because of the physical comforts it provided 51. a. the latter b. the later c. the second d. the latest 52. a source c. start d. origin 53. a. like b with d by d b. but C: moreover d fo 55. a. even if b even c even though d even as b. necessities c. necessarily 57a should gradually increase b. gradually increase c. gradually increased d has gradually increased 58. a. that b at which c which d when 59. a. with the respect b. on this respect c in this respect d. at this res 60.a. could draw b should draw c was able draw d. was drawing 61a. at which b. in which c on which d with which 62. a. of which b th which b was c. has been d is being 64 a too lon ng b such ion c as long SO long 65. a. a stage c a development b. with b b. These c. There d. They 69 a. after b with c. before d at 70exactly when he acquired the use of 51 . The 52 of language is also obscure. No doubt it began very gradually. Animals have a few cries that serve 53 signals. 54 even the highest apes have not been found able to pronounce words, 55 with the most intensive professional instruction. The superior brain of man is apparently 56 for the mastering of speech. When man became sufficiently intelligent, we must suppose that he 57 the number of cries for different purposes. It was a great day 58 he discovered that speech could be used for narrative. There are those who think that 59 picture language preceded oral language. A man 60 a picture on the wall of his cave to show 61 direction he had gone, or 62 prey he hoped to catch. Probably picture language and oral language developed side by side I am inclined to think that language 63 the most important single factor in the development of man. Two important stages came not 64 before the dawn of written history. The first was the domestication of animals; the second was agriculture. Agriculture was 65 in human progress to which subsequently there was nothing comparable until our own machine age. Agriculture made possible an immense increase in the number of the human species in the regions where it could be successfully practiced These were, at first, only those in which nature fertilized the soil after each harvest. Agriculture met with violent resistance from the pastoral nomads, but the agricultural way of life prevailed in the end because of the physical comforts it provided. 51. a. the latter b. the later c. the second d. the latest 52. a. source b. beginning c. start d. origin 53. a. like b. with c. as d. by 54. a. and b. but c. moreover d. for 55.a. even if b. even c. even though d. even as 56. a. a necessity b. necessities c. necessarily d. necessity 57.a. should gradually increase b. gradually increase c. gradually increased d. has gradually increased 58.a. that b. at which c. which d. when 59. a. with the respect b. on this respect c. in this respect d. at this respect 60.a. could draw b. should draw c. was able draw d. was drawing 61.a. at which b. in which c. on which d. with which 62.a. of which b. that c. which d. what 63. a. is b. was c. has been d. is being 64.a. too long b. such long c. as long d. so long 65.a. a stage b. a step c. a development d. a way 66.a. until b. with c. for d. to 67.a. the b. an c. that d. one 68.a. Those b. These c. There d. They 69. a. after b. with c. before d. at 70.a. since b. for c. because d. because of