Can someone check my understanding of Japanese past/present

Started learning Japanese by myself not too long ago and so far I have learned the –te iru form along with the present and past long and short forms. Getting confused about a few things, especially since it's late at night right now. Can someone just check if I understood correctly/incorrectly or missed something?

Present, present progressive, present perfect (long / short form)

1) I eat = watashi wa tabemasu / watashi wa taberu
I do not eat = wtashi wa tabemasen / watashi wa tabenai

I wake up = watashi wa okimasu / watashi wa okiru
I do not wake up = watashi wa okimasen / watashi wa okinai

2) I am eating = watashi wa tabete imasu / watashi wa tabete iru
I am not eating = watashi wa tabete imasen / watashi wa tabete inai

I am awake = watashi wa okite imasu / watashi wa okiteiru
I am not awake = watashi wa okite imasen / watashi wa okitenai (?)

3) I have eaten = same conjugation as "I ate"
I haven't eaten = watashi wa tabete imasen

I have woken up = same conjugation as "I woke up"
I haven't woken up = watashi wa okite imasen / what is the short form???

Since te imasu expresses the present progressive, do I still use 2) if I want to say "I am waking up" instead of "I am awake"? And just use the context to determine which one is being expressed?

Past simple, past progressive (long / short form)

4) I ate = watashi wa tabemashita / watashi wa tabeta
I did not eat = watashi wa tabemasen deshita / watashi wa tabenakatta

I woke up = watashi wa okimashita / watashi wa okita
I did not wake up = watashi wa okimasen deshita / watashi wa okinakatta

5) I was eating = watashi wa tabete imashita / watashi wa tabete itta
I wasn't eating = watashi wa tabete imasen deshita / what is the short form????

I was awake = watashi wa okite imashita / watashi wa okite itta
I wasn't awake = watashi wa okite imasen deshita / what is the short form????

Likewise, I'm assuming te imashita expresses the past progressive. So does 5) also express "I was waking up"?

Thanks for taking your time! J

2) "okitenai" would be a shortened version of "okite inai" - same as "tabete inai".

For okiru, 3) is really the same as 2) ("having woken up" is equivalent to "being awake"). i.e. both the polite and the short forms are the same as in 2).

The -te iru form indicates either present progressive or present perfect. Which one is meant depends on the verb: for taberu it's the former, while for okiru it's the latter (since eating takes some amount of time while waking up is a more or less instant transition from being asleep to being awake). For as far as I know it's not possible to say "I am currently waking up" in Japanese (but I'll be interested to know if I'm wrong).

5) tabete ita/okite ita with only one 't' since iru (to exist, to be present) is an ichidan verb just like taberu. "itta" could be the past form of the godan iru (to enter), iu (to say), the irregular iku (to go) etc.
Negative short form would be: tabete inakatta/okite inakatta (simply put the regular ichidan verb iru in its past form, just like tabenakatta).

Quite often just the plain form is used to mean "I am" (or am about to).
e.g. speaker is awake(-ish), but still in bed:
今起きるから (ima okiru kara)
("so wait a second/stop yelling/stop jumping on me", etc)

~ている can also indicate repeated action/habit
彼はいつもお菓子を食べている。
(kare wa itsumo okashi wo tabete iru)
He's always eating sweets.

This is quite similar to, for example
日本語を勉強している
(nihongo wo benkyou shite iru)
I study Japanese (ongoing habit, not necessarily right now)

Usually either context makes it clear, or there are time related words in the sentence - e.g. "itsumo" usually means it's about a habit.

Other expressions for "to be waking up" are 起きかけている, 起きるところだ, 起きる途中だ, 起きようとしている, 起きようとしているところだ, 起きようとしている最中だ, etc. etc....

lanthas said:

For okiru, 3) is really the same as 2) ("having woken up" is equivalent to "being awake"). i.e. both the polite and the short forms are the same as in 2).

The -te iru form indicates either present progressive or present perfect. Which one is meant depends on the verb: for taberu it's the former, while for okiru it's the latter (since eating takes some amount of time while waking up is a more or less instant transition from being asleep to being awake).

Click to expand...

Thanks! I understand better the difference between -te iru indicating either present progressive or present perfect. Just a bit hazy on the difference between using the -te iru and past tense form to indicate the present perfect. My book only says the present perfect (and present simple) in the affirmative is expressed by the past tense form. I didn't know that the -te iru form could also indicate the affirmative present perfect and not just the negative present perfect.

Are you saying that because I have woken up = I am awake (-te iru) and I have eaten = I ate (past tense form), for verbs like okiru, haku, futoru you use the -te iru to indicate present perfect instead of the past tense form which is what you would use for verbs like taberu, yomu, etc.?

I have (not) woken up
watashi wa okite imasu / imasen NOT watashi wa okimashita (which would just mean I woke up)
watashi wa okite iru / no shorter or more informal form?

I have (not) eaten
watashi wa tabemashita / tabete imasen
watashi wa tabeta / no shorter or more informal form?

The difference between present perfect "-te iru" and past "-ta" is that the result of "-te iru" is still valid at the current point in time, while "-ta" is not necessarily so. For example:
okite iru: "has woken up" (and is still awake right now). The emphasis is on the current state of being awake, rather than the past act of waking up.
okita: "woke up some time in the past" (but might be sleeping again at this point)

Or a very classic example: kekkon shite iru, "is married" (not "is currently marrying").

One important exception (that I only learned recently myself) is subclauses modifying nouns. Take the words hankachi-fu (handkerchief) and kawaku (to dry). If you write: hankachi-fu ga kawaita, it means that the handkerchief dried at some point in the past (but maybe soemone dropped it in a puddle since then). However, if you write: kawaita hankachi-fu, this should be interpreted as kawaite iru hankachi-fu, that is, a handkerchief that is currently dry. This is not always the case though; sometimes the past -ta form is really meant.

Finally, if you want to make your sentences shorter and more informal, just drop the "watashi ha". Most times it's redundant because it's clear that you're talking about yourself.

Note that the present perfect form has many functions in English grammar, and "-te iru" can't express all those meanings. For instance, 今起きました/起きたところです [ima okimashita / okita tokoro desu] is used for the prefect tense "I have just woken up now.", whereas 前に食べたことがあります [mae ni tabeta koto ga arimasu] is for experiance "I have eaten before".

Tiff said:

I have (not) woken up
watashi wa okite imasu / imasen NOT watashi wa okimashita (which would just mean I woke up)
watashi wa okite iru / no shorter or more informal form?

I have (not) eaten
watashi wa tabemashita / tabete imasen
watashi wa tabeta / no shorter or more informal form?

Click to expand...

The casual forms for "okite imasen" and "tabete imasen" are "okite inai" and "tabete inai", respectively.