證明信的英文：
【經】 letter of reference
letter是什麼意思：
n. 字母；信；字面意義；證書，許可證；文學
v. 用字母標明，寫字母於；寫印刷體字母；贏得校名縮寫字母標誌
in letter and in spirit
在字面意義和精神實質上|無論形式和實際 The letter was a forgery.
這封信是僞造的。Post the letter through the slit in the letter box.
把這封信從信箱的投信口投進去。 Imprint a postmark on a letter =imprint a letter with a postmark
蓋郵戳於信上The letter is directed to him.
這封信是寫給他的。reference是什麼意思：
n. 提到，談及；參考，查閱；證明人，介紹信
v. 查閱；參考；給（書）等附參考資料
The headmaster supplied him with a reference.
校長給他提供證明人。You can refer to a dictionary if necessary.
如果有必要，你可以參考字典。No referring back to books and notes!
不準看書和筆記！The department that you are refering to is not in existence.
你所指的.部門不存在了。The choice of the reference temperature is inconsequential
基準溫度的選擇是無關緊要的。
