簡單問題......has/have幾時用.....

A) 要考慮用於那些subject? e.g.
He/ She/ It/ Everyone has some problems.
I/ You/ We/ They have some problems.
Indefinite pronoun
http://www.infoplease.com/cig/grammar-style/indefinite-pronouns.html
Singular: everyone, everything, each of them, one of them, none of them ... (用has)
Plural: some of them, most of them, many of them, all of them, both of them ... (用have)
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B) 當佢係auxiliary verb的身份, 佢就要因應不同情況而運用於不同的時式 (tenses)
Present Perfect tense
1) Have you been to Hong Kong Disneyland? 你曾經去過廸士尼嗎?
2) She has never been to Japan. 她從未到過日本。
Present Perfect Continuous tense
1) They have been living here for ten years. 他們一直住在這裏已經十年了 (現時仍然在這裏居住)。
2) He has been studying in England for one year. 他一直在英國留學已經有一年了 (現時仍在英國)。
Future Perfect tense
1) We will have left when you arrive. 你到達時, 我們將會已經離開 (但現時未到)。
2) It will have escaped before you react. 在你未有任何反應之前, 牠將會已經逃走了 (牠未開始逃走, 但這是說話者認為最有可能的假設/ 結果)。
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C) 當has/ have 用作 main verbs
If you have any problems, please feel free to contact me.
He has his own style. 他有自己的個人風格。

圖片參考：http://tw.yimg.com/i/tw/ugc/rte/smiley_1.gif


2008-09-27 03:36:11 補充：
Each of them, one of them, none of them 為何用has呢?　(為何them不用have呢?)

睇過以下例子就明白:
http://www.youtube.com/watch?v=03a1Bel3V3w
None of them is you.

http://www.guardian.co.uk/technology/blog/2006/jan/05/thequizfinal
None of them is 42.

2008-09-27 03:36:25 補充：
因為has係指"None of",唔係指them, none of them 之中的none of,係解no one, 即「無任何一個人」, 而no one又如何會用 plural "have"呢?

I, You, We and They - have

She, He - has

have 係第一/二生或眾數現在式, 即 I, You, We, They 之後用

has 係 have 的第三生單數現在式, 即 He, She, It, 或 人/物名之後用