根据下面一副对联的上联选出最好的下联。
上联:学海里遨游你追我赶
下联:__________________
—Do you like the story?
—Yes,I like it, my sister doesn't.
宏伟的长城是我国古代劳动人民智慧和独创性的象征,秦长城的起止点是( )