She didn't like the work,because it lacked variety;she was doing the same things all the time Variety is the spice of life.(-oing a lot of different things,meeting different people etc is what makes life interesting. Word formations:vary (v.)various(a)varied(a)variable(n&a)variation(n)varia (n.) More exercise: 1)Directions:Fill in the blanks. 1)Customsfrom country to country.(vary) 2)Human nature,in all its many and forms,is very complex and hard to understand varied) 3)Of all theways of cooking an egg.I like boiling best.(various) 4)There are wide regionalin house price.(variations) 5)There are too many in the experiment to predict the result accurately.(variables) 6)Consumers'preferences are sothat planning is almost impossible.(variable) 2)Translation: (①)风俗随国家不同而有所变化。 (2)人类本性，多种多样，变化多端，复杂难解。 (3)在各种各样做鸡蛋的方法中，我最喜欢煮鸡蛋。 (4)房价有很大的地方性差异。 (⑤)实验存在太多的变量，无法准确预测实验结果。 (⑥消费者的喜好是如此反复无常以致于不可能形成什么计划 7.revolve v.a to spin around or make sth.spin around,ona central point b.(fig.)to think about Examples The metal disc revolves at high speed. The earth revolves round the sun. The story revolves around a young girl who runs away from home He revolved the matter in hishead/mind. Synonyms:spin rotate whirl 8.present a v.(reflex)to appear,attend Examples: When the chance to study at Harvard presented itself.I jumped at it.She didn’t like the work, because it lacked variety; she was doing the same things all the time. Variety is the spice of life. (=Doing a lot of different things, meeting different people, etc. is what makes life interesting.) Word formations: vary (v.) various (a.) varied (a.) variable (n. & a.) variation (n.) variant (n.) More exercise: 1) Directions: Fill in the blanks. 1) Customs _ from country to country. (vary) 2) Human nature, in all its many and _ forms, is very complex and hard to understand. ( varied) 3) Of all the _ ways of cooking an egg, I like boiling best. (various) 4) There are wide regional _ in house price. (variations) 5) There are too many _ in the experiment to predict the result accurately. (variables) 6) Consumers’ preferences are so _ that planning is almost impossible. (variable) 2)Translation: (1) 风俗随国家不同而有所变化。 (2) 人类本性，多种多样，变化多端，复杂难解。 (3) 在各种各样做鸡蛋的方法中，我最喜欢煮鸡蛋。 (4) 房价有很大的地方性差异。 (5) 实验存在太多的变量，无法准确预测实验结果。 (6) 消费者的喜好是如此反复无常以致于不可能形成什么计划。 7. revolve v. a. to spin around or make sth. spin around, on a central point b. (fig.) to think about Examples: The metal disc revolves at high speed. The earth revolves round the sun. The story revolves around a young girl who runs away from home. He revolved the matter in his head/mind. Synonyms: spin rotate whirl 8. present a. v. (reflex) to appear; attend Examples: When the chance to study at Harvard presented itself, I jumped at it