答案解析：
36. aggravates
解析：根据本句的主语及整篇文章的时态来看，可知此处需要填入动词的第三人称单数形式，作句子的谓语，aggravate“加重”，注意要双写s。
37. acquire
解析：空格前的情态动词may表明该词应该是动词原形，acquire“获得”，注意不要漏掉中间的字母c。
38. relief
解析：填入的词与benefit并列，因此此处需要一个名词，可以根据发音规则拼写。
39. manual
解析：此处需要填入形容词，修饰labourer，manual labourer意为“体力劳动者”。
40. sweat
解析：此处应该填写一个名词，和effort并列，sweat“汗水”，此词很好拼写。
41. professional
解析：根据并列结构及空格前的定冠词the，可知此处应填写名词，注意双写s。
42. trivial
解析：修饰名词往往用形容词。trivial指“琐碎的”。
43. rational
解析：根据上下文，此处应该填写与hard-working，useful并列的褒义形容词，rational“明事理的”。
44. 标准答案：first, those whose work is work and whose pleasure is pleasure; and secondly, those whose work and pleasure are one
听音关键：work is work，pleasure is pleasure，work and pleasure，one
答案重构：first, those whose work and pleasure are divided, and secondly, those whose work and pleasure are one
画龙点睛：由本段第一句可预测本句是对两种人的详细介绍。本句关键是理解几个定语从句的意思，前半句的定语从句可简化成whose work and pleasure are divided。
45. 标准答案：The long hours in the office or the factory bring with them as their reward
听音关键：long hours，office，factory，bring，as，their reward
画龙点睛：该句结构及用词都不难，不建议改写，原词照搬即可。
46. 标准答案：Their life is a natural harmony. For them the working hours are never long enough
听音关键：life，natural harmony，working hours，never，long enough
答案重构：Their life is a natural harmony and their working hours are never long enough.
画龙点睛：该句由两个简单句构成，可以将其合并成一个并列句，层次可更清晰，语句也更简洁。