a short period during which（during which 定语从句修饰period,意思是一段怎么样的时期） sth different happens from what is happening the rest of the time（后一句中different from构成短语,表示不同于.把hap... a short period during which（during which 定语从句修饰period,意思是一段怎么样的时期） sth different happens from what is happening the rest of the time（后一句中different from构成短语,表示不同于.把hap...