Period Ⅱ Using language——Grammar & Vocabulary Grammar(定语从句 2)课前自主预习[观察句子,总结规律]①Somehow they manage to travel around 4,000 kilometres south and find their way to places where they will spend the winter.②The solution to the mystery of the monarch's amazing ability comes at a time when it is in serious trouble. ③Unfortunately, human activity is the main reason why the monarch numbers are falling.[我的发现]通过观察可知:(1)句①中定语从句的引导词是关系 ,在定语从句中充当 状语,定语从句修饰表示 的名词 places。(2)句②中定语从句的引导词是关系 ,在定语从句中充当 状语,定语从句修饰表示 的名词 time。(3)句③中定语从句的引导词是关系 ,在定语从句中充当 状语,定语从句修饰表示 的名词 reason。答案:(1)副词;地点;地点 (2)副词;时间;时间(3)副词;原因;原因精讲课时语法关系副词的用法(1)when 指时间,在从句中作时间状语。先行词通常为表示时间的名词,如:time, day, week, year 等。I cannot forget the day when I first saw you.我永远不会忘记第一次见到你的日子。(2)where 指地点,在从句中作地点状语。先行词通常有:place, street, house, city, country 以及一些抽象意义的名词,如 point, case, position, condition, situation 等。This is the house where they lived a week ago.这是一个星期前他们住过的房子。(3)why 指原因或理由,先行词只有 reason。The reason why she did it is still a mystery.她为什么做那件事仍是一个谜。名师点津 (1)这三个关系副词在意义上都相当于“介词+which”结构:1①when=on (in, at, during ... ) +which②where=in (at, on ... ) +which③why=for which(2)当先行词是表示时间的 time, day 等或表示地点的 place, house 等时,一定要注意分析从句的结构,如果缺少主语或宾语,关系词应用 which 或 that,缺少时间状语或地点状语时,才能用 when 或 where。I still remember the day (which/that) we spent together in the city.我仍然记得我们在那座城市一起度过的那一天。This is the room where (in which) Lao She once lived.这是...