tense~~

現在式- simple present tense (verb) I / you/ they唔洗加s, He/ she / it 要加s, 因為係third person singlar, 第三身單數
ex: I go to do shopping everyday.
點解會用go, 咩都唔洗轉呢, 因為這是true for long time 或者all time 既事實, 不會變改的,又或者人地問你, where are you from? 一定是答i m from hk, 而唔會係 i was from hk, 因為你係香港人,永遠都係, 唔會改變的. 所以就用現在式.

過去式- simple past tense (verb, past tense)
ex: I went to the beach with John just yesterday.
呢個比較易明, 因為是以經發生的事, 所以要用past tense, 但係通病就係一般人都比較懶, 唔肯背時式表, 有d 動詞後面唔一定係就咁加ed, 呢個要你自己研究一下了

現在進行式- present continous tense (is am are + verb + ing)
ex: What's john doing down there? Oh, he is repairing his bike.
呢個都係比較易明, 只係用係動作進行中既時候. 但係~~ 一般人都會忽略佢重有另一個用法, 就係present continous tense 亦都可以意味將來以經預料會做的事
ex: Hei, Mary, i just wanna tell you i am going to john's house to stay overnight next Sunday, can i?
這是你原本以經計劃好的事, 將來亦會發生.

過去完成式- past perfect tense (had+ pp)
ex: When i came back home, John had cooked tea already.
呢個時式你要用一把間尺方便自己啦~ 尺中間代表現在~now, 前少少就係過行式past tense, 再前d 就係past perfect tense 啦, 點解呢, past perfect tense 係一定用黎說明比過去更早發生既事情, 像剛剛的例子, 當我回到家, John 以經煮好茶.

過行進行式- past continous tense (was were + verb + ing)
ex: What were you doing at 8 last night? oh, i was taking shower
呢個係用係過去某段時間, 發生緊既事情, 不是太難的

現在完成式- present perfect tense (has, have + past participle)
ex: How long have you been in Australia? Oh, i have been in here for 2 years already.
呢個時式係用係從過去發生到現在, 而將來亦都會發生既動作, 就像例子, 你來了澳洲多久? o~我宜經來了這裡兩裡了, 當然, 我會繼續係澳洲, 所以就要用present perfect tense 啦.

現在完成進行式- present perfect continous tense (has, have + verb + ing)
ex: How long have you been smoking for? eh~~ i hav been smoking for a year already.
呢個時式同現在完成式非常相似, 但係當你明白到呢個時式既時候, 你會發現那一個比較貼切, 基本上, 你答i have smoked for a year already, 都係冇問題的.


Future tense- 將來式 (will + verb)
將來式明顯是用黎說明將來會發生既事, 但係, 將來式跟現在進行式的意思卻有所不同~
ex: john dropped down his pencil carelessly, and he was gona pick it up, but suddenly, i said, i d pick it up for you, which mean john didn't expect me to pick up his pencil for him.
意思說明了~ 將來式亦意味著不是本人預期會發生的事或動作.


希望幫到你吧~^.^

maybe you can參考:
http://www.npc.edu.hk/staff/~ngtungying/english_grammar/

Tense分了三大類,一類裏又分了三小類

_______________ present simple tense(verb)
present tense_______________ present continuous tense(is/am/are+(verb+ing))
present perfect tense(have/has+verb)

__________________ past simple tense (verb)
past tense__________________ past continuous tense(was/were+(verb+ing))
past perfect tense(had+verb)

_________________future simple tense(will/(is/am/are going to)/shall+verb)
future tense_________________ future continuous tense<............>
future perfect tense<.............>

2007-02-23 17:36:53 補充：
參考資料: Learners English Keys & Exercises 英文精讀與練習

present simple
-Talk about facts.
-Talk about things that are always true(universal truth)
-Talk about habits and things that happen regularly(routine)
-Give orders and instructions.

present continuous
-Things happening at or around the time of speaking.
-Arrangements or plans in the future.
-Action shown in pictures and potos.

simple past tense
-For an action which happened in the past. The action finished completely by the time
of speaking.
-For a habitual action in the past.


past continuous tense
-A past action which was going on at a definite past time.
-A past action which continued for a certain period of time.
-An action which was going on when another action took plance.
Two long actions which were going on at the time in the past.

present perfect tense
-Sometimes that happened in the past and is related to the persent.
-Sometimes that happened a short time age.

future
-What we plan to do but we are not sure about it.
-A furture action when the time is not definite.