What is the difference between まだしません and まだしていません?


These are the two sentences in question:

> いいえ、まだしません。
>
> いいえ、まだしていません。

From my understanding they both mean something like "No, I didn't yet" or even
simply "No, not yet" but there must be a difference in translation/meaning or
application that I'm missing obviously based around the ています which is present
continuous correct?




The meaning of these two sentences is likely to be different.

_Plain negative:_

> (1) いいえ、まだしない。  
>  "No, (I) do not do it (habitually) yet." _(yet: habitual)_  
>  "No, (I) will not do it yet." _(yet: habitual)_  
>  "No, (I) still do not do it (habitually)." _(still: habitual)_  
>  "No, (I) still will not do it." _(still: future)_

_Negative ている:_

> (2) いいえ、まだしていない。  
>  "No, (I) have not done it yet." _(yet: stative)_  
>  "No, (I) am not doing it yet." _(yet: progressive)_  
>  "No, (I) am not doing (habitually) it yet." _(yet: habitual)_  
>  "No, (I) still have not done it." _(still: stative)_  
>  "No, (I) am still not doing it." _(still: progressive)_  
>  "No, (I) am still not doing it (habitually)." _(still: habitual)_

**Examples:**

> 「宿題は終わった？」 "Did you finish your homework?"  
>  「いいえ、まだしていません。」 "No, I haven't done it yet." _(yet: stative)_

`まだしません` would be wrong here, because that would mean "I am not doing my
homework (regularly/habitually) yet.", or "No, I am still not going to do my
homework (regularly/habitually)." or "No (I) am still not going to do it."
none of which are an answer to the question.

> 息子はまだ（毎日）歩かない。  
>  "My son does not walk (every day) yet." _(yet: habitual)_  
>  "My son still does not walk (every day)." _(still: habitual)_
>
> （昨日から）息子はまだ歩いていない。  
>  "My son has not walked yet (since yesterday)." _(yet: stative)_  
>  "My son still hasn't walked (since yesterday)." _(still: stative)_
>
> （立ち上がったばかりなので）息子はまだ歩いていない。  
>  "(My son just stood up a second ago,) so he is not walking yet." _(yet:
> progressive)_  
>  "(My son just stood up a second ago,) so he still is not walking." _(still:
> progressive)_
>
> 息子はまだ（毎日）歩いていない。  
>  "My son is not walking (every day) yet." _(yet: habitual)_  
>  "My son is still not walking (every day)." _(still: habitual)_

Here is an example sentence which allows all the different interpretations. I
use some extra pieces of text to help disambiguate the ていない sentences
semantically. (I couldn't think of a nice example for する that allows all
interpretations, so I went with 歩く instead -- I hope this isn't confusing.)




The meaning of these two sentences is likely to be different.

_Plain negative:_

> (1) いいえ、まだしない。  
>  "No, (I) do not do it (habitually) yet." _(yet: habitual)_  
>  "No, (I) will not do it yet." _(yet: habitual)_  
>  "No, (I) still do not do it (habitually)." _(still: habitual)_  
>  "No, (I) still will not do it." _(still: future)_

_Negative ている:_

> (2) いいえ、まだしていない。  
>  "No, (I) have not done it yet." _(yet: stative)_  
>  "No, (I) am not doing it yet." _(yet: progressive)_  
>  "No, (I) am not doing (habitually) it yet." _(yet: habitual)_  
>  "No, (I) still have not done it." _(still: stative)_  
>  "No, (I) am still not doing it." _(still: progressive)_  
>  "No, (I) am still not doing it (habitually)." _(still: habitual)_

**Examples:**

> 「宿題は終わった？」 "Did you finish your homework?"  
>  「いいえ、まだしていません。」 "No, I haven't done it yet." _(yet: stative)_

`まだしません` would be wrong here, because that would mean "I am not doing my
homework (regularly/habitually) yet.", or "No, I am still not going to do my
homework (regularly/habitually)." or "No (I) am still not going to do it."
none of which are an answer to the question.

> 息子はまだ（毎日）歩かない。  
>  "My son does not walk (every day) yet." _(yet: habitual)_  
>  "My son still does not walk (every day)." _(still: habitual)_
>
> （昨日から）息子はまだ歩いていない。  
>  "My son has not walked yet (since yesterday)." _(yet: stative)_  
>  "My son still hasn't walked (since yesterday)." _(still: stative)_
>
> （立ち上がったばかりなので）息子はまだ歩いていない。  
>  "(My son just stood up a second ago,) so he is not walking yet." _(yet:
> progressive)_  
>  "(My son just stood up a second ago,) so he still is not walking." _(still:
> progressive)_
>
> 息子はまだ（毎日）歩いていない。  
>  "My son is not walking (every day) yet." _(yet: habitual)_  
>  "My son is still not walking (every day)." _(still: habitual)_

Here is an example sentence which allows all the different interpretations. I
use some extra pieces of text to help disambiguate the ていない sentences
semantically. (I couldn't think of a nice example for する that allows all
interpretations, so I went with 歩く instead -- I hope this isn't confusing.)

