look back to 回頭看，表示身體回轉(zhuǎn)，看什么東西

　　例如：When I look back to my childhood I can best recall the rainy days.

　　當(dāng)我回顧我童年生活的時(shí)候，下雨的日子給我印象最深。

　　look back at 回頭看，注意力集中于

　　例如：I will look back at this one with undiluted pleasure.

　　回顧此事，我會(huì)無比地開心。