Past Tense
Once you know how to form the present tense, past tense is easy. Remember
how you changed the verb before adding 
? In case you don’t,
here it is:
Group 1: Change final 
sound to 
Group 2: Drop final
Group 3:→
; 
→
sound to Group 2: Drop final
Group 3:
→; →
Instead of adding to form the present, add
to form the past.
For negative sentences, instead
of adding 
, add 
.
Some Examples
Group 1
| Verb | Changes to… | Sentence |
|---|---|---|
  (to drink) |
 |
       The dog drank water.   The cat did not drink water. |
 (to write) |
 |
    Mori-san wrote a letter.   Tanaka-san did not write a letter. |
Group 2
| Verb | Changes to… | Sentence |
|---|---|---|
 (to eat) |
|
    Aoki-san ate rice.  Satō-san did not eat rice. |
  (to find) |
|
  I found the book.   I did not find the magazine. |
Group 3
| Verb | Changes to… | Sentence |
|---|---|---|
(to do) |
|
  [I] did the homework.  [I] did not do the exercise (for the reader). |
(to come) |
|
  The mail came (arrived).   He did not come to Tokyo. |