He talked about a hero _______ no one had ever heard.
His parents told him ________ too much about what others said.
________ his appearance, he is most probably a new teacher.
After teaching in Bejing for five years, he returned to the small town ________ he grew up as a child.
He devoted all his life to ________ those who are suffering from cancer.
Gone are the days ________ China was called “a Sick Man of East Asia”.