senior [?si?ni?(r)] adj. ①资格较老的，地位较高的②年长的，高年级的 n. ①较年长者 ②（中学或大学的）毕业班学生，上级，长辈，高年级生
例句　Leng Xiwu, a senior engineer in Beijing, was surprised at McDonald’s increasing its prices. 北京的一位高级工程师冷昔伍对于麦当劳提价之举感到十分惊讶。
翻译　I am a senior student.（我是一名大四学生。）
同义替换　adj. ②older; elder
series [?s??ri?z] n. ①一系列，连续 ②（电视）系列片
例句　Privacy economist Alessandro has run a series of tests that reveal people will surrender personal information like Social Security numbers just to get their hands on a pitiful 50-cents-off coupon（优惠券）.