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76．She took lots of beautiful 　　during her stay in Europe．

77．Tom，believing in 　　is the first step on the road to success．

78．Tomorrow will be 　　．How about going to Mount Gu for a picnic？

79．The teacher kept 　　the use of the idiom to me until I understood it．

80．He was facing a difficult 　　between staying with his family or working in Tibet．