Have的用法?

A. 動詞方面有兩種：連綴動詞及動作動詞。很明顯動作動詞就是表示主詞「在做甚麼」。致於連綴動詞就是表示主詞「是甚麼」。Have 作動作動詞時，是「擁有」的意思，並沒有中文「有」的另一個「存在」的意思。要有「存在」意思，該用 'be'。
e.g. There is a dog. <-- A dog is over there.

B. Have 作輔助動詞時是沒有字意。動詞的時式 (tense) 告訴我們事情何時發生。have 在主要動詞前作完成式，而主要動詞變作過去分詞時，那就是作完成式。
完成式(現在/過去)：(has/have/had) + verb (past participle過去分詞)
e.g. I have/had swum.

Present Perfect --
1. 結束/結果(剛剛)
e.g. I have become a teacher.
現在仍是老師。
比較： I became a teacher 3 years ago.
在三年前成為一位老師。成為老師這個轉變在三年前發生，所以用 simple past。
e.g. I have finished my homework already.
比較： I finished my homework hours ago.

2. 完結但影嚮至今的動作；繼續
(hints：會有表示一段時間的副詞出現)
e.g. I have lived here for 5 years.
5年前就遷入了，現在還住這裡呢。
e.g. I have come to this school since Form 1.

3. 經驗
(hints：會出沒有明確時間的副詞出現。如：often, before, never, since ...)
e.g. I have never been to a cinema before.
從未體驗過去戲院。

Past Perfect -- 簡單而言，在過去(必須與現在已無關聯)有兩個動作發生了，你猜怎樣分別哪個動作先作？對了。past perfect 表示動作比 simple past 先做。即如果句子只有一個動詞，用 simple past 已可以了！
(hints：會出現 already, recently, just ...)
e.g. Mary said that she had already finished her work.
當然是做好功課先 Mary 才說話。

C. 還有一種叫情態動詞： must, can, may ...
*** be, do, have* 本身亦可作有字意的主要動詞，可要留意啊！
I was young. / I am talking to John.
I do the dishes. / I do not do the dishes.
I [have] (擁有) a dog. / I [have to] (必須) go now.

have 標示解釋
圖片參考：http://hk.yimg.com/i/dic/043.gif
]
DJ: [
圖片參考：http://hk.yimg.com/i/dic/043.gif
]
v.aux. 1. (加過去分詞,構成完成時態)已經;曾經 They haven't finished the job yet. 他們尚未完成該項工作。 2. (用於假設語氣,表示與過去事實相反的假設)(假如那時)...的話 She might have come if she hadn't been so busy. 當時若不是那麼忙,她是可能來的。 vt. 1. 有,擁有[W] This coat has no pockets. 這件衣服沒有口袋。 2. 懷有,持有[W] Many people have doubts about the new project. 許多人對這項新工程有懷疑。 3. 體驗;經驗;患[W] We had a wonderful time on the beach. 我們在海灘上玩得好極了。 4. 拿;得到,取得[W] We gave him a present, but he wouldn't have it. 我們給他一件禮物,但他不肯接受。 5. 進行,從事(某事) The manager is having a meeting. 經理正在開會。 6. 吃;喝;吸(煙) They had their lunch in a cafeteria. 他們在一家自助餐廳吃了午飯。 Have a cup of coffee, please. 請喝杯咖啡。 7. 邀請(某人),招待[O] We had some guests for dinner last night. 我們昨晚請了幾位客人吃飯。 8. (用於否定句中)容忍;允許[O4] I won't have anyone smoking in here. 我不容許任何人在這裡抽煙。 9. 生得,生育 My wife is going to have a baby. 我妻子快要生孩子了。 10. 使,讓;招致[O7][O8] Pa's had his hands burned. 爸的手給燙傷了。 I've had the stove lighted. 我已經讓人把爐子點著了。 11. 要;叫;使[O3][O4] I'll be proud to have you read it. 你肯讀它我會感到驕傲的。 12. 必須,不得不[+to-v] I have to go right now. 我馬上得走。 13. 【俚】哄騙,欺騙[H] They were had in that deal. 他們在那筆生意上受了騙。 14. 明白,懂得[W] I guess I have your ideas. 我想我明白你的意思。 15. 【俚】與(女人)性交 n. 1. 富人;富國[the P] The gap between the haves and the have-nots is widening. 貧富之間的差距在擴大。