Gammar一問送十分

1. Have got / have
Have got 和 have 意思分別其實不大, 分別是 have got 是 past perfect tense, 代表「得到了」, 而 have 是 simple present tense, 代表 「擁有」。比如:
- I have a cat.
- I have got a cat.
第一句單純是「我有一隻貓」的意思。第二句可以是同樣意思, 也可以看成是「我得到了一隻貓」, 要看前文下理。不過很多情況下, 兩者不需要區分。

2. Will be doing / will have done
首先分開兩者的 tense. Will be doing: future continous tense 「將會在做」; will have done: future perfect tense 「將會做完」留意 perfect tense 是「完成式」, 有「完成了一件事」的意思。所以:
- Tomorrow I will be doing my homework.
- Tomorrow I will have done my homework.
第一句就是「明天我會在做功課」
第二句是「明天我就會做完了功課」, 是完成了的意思。

3. When I do / when I have done
類同, 也是 perfect tense 的分別。留意「完成了」的意思就不難明白了。
- When I do my homework, I can't watch TV.
- When I have done my homework, I can watch TV.
第一句: 我做功課就不能看電視
第二句: 我做完了功課就可以看電視

4. when / if
when 是帶有時間性的, 大概等於「當...的時候」, 而 if 就是「如果」。兩者都可以用於假設性句子, 但 when 是假設將來的事, 有一部分是交代時間的; if 就是整句都是假設。
- When I was watching TV, the telephone rang. (非假設性)
- When I grow up, I will be rich. (假設性; when I grow up "當我長大了的時候" 交代時間)
- If I am hungry, I will eat. (本身不是肚餓 --> 全句都是假設)

5. Can, could, be able to
意思都是「可以」, 但有細微的分別:
could 可以是 can 的 past tense; 在提出請求時, could 比 can 禮貌。
- Can you open the door?
- Could you open the door?
另外在說「如果那時我.... 就可以....」的假設性問題時不會用 can, 只會用 could.
- If I had bought the dress, I could have worn it to the party.
如果那時我買了那條裙, 我就可以穿著它去派對了。

Can 和 be able to 的分別: can 是「可以」, be able to 是「有能力」, 即是說一個人可以有能力做一件事 (able to), 但不想做 (cannot).

6. Could / could have
假設性問題有分幾種, 最常見的有
a. Real - 很有可能發生的事, 會用 simple present tense.
If I am hungry, I will eat.
b. Unreal present - 沒太多機會發生的事, 會用 simple past + would
If I were rich, I would buy a big house.
c. Unreal past - 想改變過去的事 (當然沒可能了) 會用 past perfect + would/could/might/should + present perfect
If I had bought the dress, I could have worn it to the party.
但一定不可以只用 could.

希望幫到你啦! 我自己的英文其實是看很多英文書累積下來的, 並沒有認真的讀過 grammar, 所以上面的解釋寫得很差 (自己明白, 但不懂解釋)
我不知道你可以用多少時間改善英文, 但最 effective 的方法一定是多看, 直到用英文 grammar 不用花時間想「為什麼是用這種 grammar」看書也好, 雜誌也好, 報紙也好, 總之一定要多。我以前上英文課時就是偷偷在抽屜裡看英文書....... 從不溫習英文.... 結果 CE & AL Eng 還是 straight A 了啦.......

Can,Could and (Be)able to

can可以用係一d野有可能發生或指一些人有能力可以做到

通常can+infinitive(e.go,see)

can同(be)able to差不多,也指一些人有能力可以做到一d野

不過,can比較常用一d 而且(be)able to 也比較深(我建議唔好用)

[2種用法:can/could,但是(be)able to 有好多用法:is/am/are/has/
have/has,have+been]

比較can同(be)able to:

e.g I can't sleep -> I haven't been able to sleep recently.

Could

could係can的過去式,所以could也有這樣用法

e.g I couldn't hear very well.What did you say?

仲有could也可指一d人在過去時有能力或做到一d野

e.g My grandfather could speak 5 languages(語言).

可是,當你所指的是一d人在過去特別既情況下做左一d既野,要用was/were able to (唔好用could)

e.g We didn't find where David was,but we were able to find him in the end(最初穩唔到 David ,不過最後穩番佢)

2006-12-08 04:55:33 補充：
加番比較Could同 (be) able to e.g Mike was an good tennis player when he was younger.He could beat anybody(意指佢曾經可以打低任何人) Mike and Pete play tennis yesterday.Pete played very well,but Mike was able to baet him.(意指佢在昨天的比賽中打低了Pete)(這2篇野打足1粒鐘)@.@

2006-12-08 05:02:28 補充：
[2種用法:can/could,但是(be)able to 有好多用法:is/am/are/has/have/has,have been]|v[2種用法:can/could,但是(be)able to 有好多用法:is/am/are/was/were/has/have/has,have been]