Meet vs. See

[男生在路上見到他認識的人。跟那個人聊以後就說了 "Bye! Nice to meet you!“] .......講錯！

[商人在開會突然遇到以前的顧客。晚上寫了一個 email 跟顧客說 "It was nice to meet you again!"] .......也不對！

為什麼呢？
因為 "meet" 的意思是 ”認識“ 而且，當你第一次遇到某人才可以用這個字.

那，已經見過那個人的話可以說什麼？

"Nice to see you!"
"Nice to see you again."
"It was nice to see you again."
"It was nice seeing you again."
"It was a pleasure to see you again."
"It was good to meet up with you again." [<--- "meet up" 的意思是“遇到”]
"It was nice running into you again." [<--- 或 "to run into" = 突然碰到. 也可以用 "bumping into" 或 "to bump into"]

面對面 / 都可以 / 正式 / 俚語