obtain 和 get 如何用？兩者有何分別？

OBTAIN 是較 formal 的字, 正如第一位朋友所說, 有獲得之意.
現附上及補充 Cambridge Dict. Online 的觲釋及例句如下:

解釋: to get something, especially by
1) requesting it,
2) buying it,
3) working for it,
4) or making it from something else:

例句:
1) to obtain permission
(比 get permission 客氣, 而且你不是自己要有便一定有的)
2) First editions of these books are now almost impossible to obtain.
(此句用 buy 來取代 obtain, 比較用 get 好)
3) In the second experiment they obtained a very clear result.
(是經過實驗才得到的)
4) Sugar is obtained by crushing and processing sugar cane.
(是從另一物質提煉的)

obtain (vi) 另一個意思是存在 (但此用法我們平時較少用到):
Conditions of extreme poverty now obtain in many parts of the country.

GET 除解作得之外, 還有其他廣泛的用途. 你的問題應是得之意的分別, 故不詳述.
(e.g. get + past participle --- get married, get your work done etc.)

2006-12-13 11:22:01 補充：
http://dictionary.cambridge.org/define.asp?key=54806&dict=CALD

2006-12-13 11:33:24 補充：
例句4如果用get來表達便很不自然 (Sugar is got by crushing ....). 若要用get, 便應用主動式: WE can get sugar by crushing and processing sugar cane.

2006-12-17 16:24:54 補充：
you are welcome

Obtain - 得到,獲得
e.g. He obtained a scholarship.
他獲得獎學金。

Get - 獲得;得到;贏得
e.g. He got first prize in the listening contest.
他得到聽力比賽第一名。

They mean the same but the word 'obtain' will be more FORMAL/SCIENTIFIC, the word 'get' is more INFORMAL/CASUAL