requested 同 required 的分別

分別:
Required 需要,可能是命令 (order), 规定,法律,規則,合約上需要
Required (verb) = needed/wanted someone or something

If a rule, law or contract requires (命令, 规定) something, you must do that thing
You are required to wear seat belt when driving. (~ 交通規則)

Requested 是請求 (多數下级對上级）, 索取;邀请 ~ 有禮貌,謙恭地
Requested (verb) = asked for something or asked someone to do something politely or formally

(1) used as past participle:
Guests are requested to register at the front desk. (因為是客人,來賓,用 requested)
First year students are required to register by Friday, September 3. (因為大學規則,用 required)

(2) used as past tense:
Working with children required a lot of patience in the old days.
The captain requested the pleasure of your company at dinner last night. (~ formal invitation)

(3) used as adjective:
Required = 必需的 (adj.) [required reading = 應閱讀的]
Requested = 被請求的 (adj.)

The bill failed to get the required number of votes.
I enclose the requested information.

題外:
如果沒有–ed, require 是verb, request 除了做 verb 外, 還是 noun



2012-11-07 08:54:43 補充：
Note that when request is a verb, you do not use "for" after it.
(only when request is a noun)
The pilot requested permission to land.
Request for permission to land was granted.

request係邀請，require係需要，完全唔同﹗