點解Simlp pas要加ed或d????

The past tense,past events, and things were different in the past that simple past tense as an adjective,not the future tense, referring the matter to add --ed or ---d has to be learnt from the past times of English Grammar re:past tense.
(1)We simply add -ed to words ending in double consonants:-eg. add and hand (2) to those ending in w: eg. allow and (3) to those ending in single consonant preceded by double vowels: eg. appear and join.
(4) We only add -d to verbs ending in e:- eg. agree,change,complete,lie, where "chang+--ed"=by Rule (1) is incorrect,whilst "change+ -d"=by Rule (4) is correct!
(5)We double the final single consonant preceded by a single vowel before adding --ed:- eg.dig,drop,and fit;whilst "dwell+ed"=by Rule (1) is correct,while "dwelled"=by Rule (5) is incorrect!
Here are some more eg.in the 5 classifications for you to learn:-
Class(1) added, handed, jumped, talked, walked,
Class(2)allowed
Class(3)appeared, joined, waited,
Class(4)agreed,behaved, cared, carried, changed, completed, cried, lied, replied, tied,
Class(5)digged, dropped, fitted, knitted, smelled, spelled,
So linguistic terms syntax is grammar which you learn in school.

2012-03-03 21:38:50 補充：
An innovation has become new features(dely)for dealt,(dreamed)for dreamt,(dwelled)for dwelt.Past&Past Participle don't just added -ed or -d for the past.I've seen several comments about the way I responded.Thanks for your observations.

"Digged" is the older past tense and past participle of "dig". The modern form "dug" is an innovation that has become standard.- http://en.wiktionary.org/wiki/digged

To 回答者：TOMING88 :

Where do you find the word "digged" ?

The past tense of "dig" is "dug" .
Please check your dictionary.

因為係文法，你需要知，你需要識，無須解釋，就如同你個名，你話點解﹖

因為要區分佢既tense,
如:reported,report咁
係verb入面後面帶ed既通常都係過去式
就咁加d係因為動詞後面己經有e
但唔代表後面有e既動詞就一定會以加d既方式轉tense
如:write變wrote咁
加ed只係轉tense既其中一種變化

2012-02-25 14:26:19 補充：
仲有一個原因,你可以去問造英文個個人點解