誰はしました。Who did it?


I'm aware that する is the Japanese verb "To do". In order to conjugate this
verb using the Ta form for past tense we of course just replace する with し and
add our polite form ます with the た to make しました, so my question is this.

Does this logically make sense to a native Japanese person? If I want to know
"Who did it?" as in "Who committed the crime?", "Who did the thing?" etc. Is
this sentence really that simple?




As you might have learned with respect to the は in the phrase, the Japanese
language, and specifically its grammar, is driven by a system of particles. In
this case, you have probably yet to learn that there is a particle that
corresponds to questions. This is the か particle, and is placed at the end of
a sentence or phrase that is meant to be a question. Consider its use to be
similar, but not exactly the same, as using a question mark in the English
language, and it is voiced.

The か particle transforms a statement into a question, like so:

> これはあなたのえんぴつです。  
>  This is your pencil.
>
> これはあなたのえんぴつです **か** 。  
>  Is this your pencil?

Note that all that changed was the addition of the か particle at the end.

In the case of your not-yet-a-question statement, you'll need to do the same:

> だれはしました **か** 。  
>  Who did it?

This is technically ungrammatical, so you'll need another particle here: the が
particle. This particle generally marks the direct subject of the sentence. In
this phrase, it replaces the は particle (which can be considered a "topic"
particle). Question words in question sentences are automatically the explicit
focus of the sentence, so they take the が particle instead of は, when asking a
question.

Putting it all together, then we have:

> だれ **が** しましたか。  
>  Who did it?

Now this sentence is grammatically correct. There are still more natural ways
to express this question, especially depending on the context you'd be asking
it in, but without a little more studying from your part, this is as good as
this will get.




As you might have learned with respect to the は in the phrase, the Japanese
language, and specifically its grammar, is driven by a system of particles. In
this case, you have probably yet to learn that there is a particle that
corresponds to questions. This is the か particle, and is placed at the end of
a sentence or phrase that is meant to be a question. Consider its use to be
similar, but not exactly the same, as using a question mark in the English
language, and it is voiced.

The か particle transforms a statement into a question, like so:

> これはあなたのえんぴつです。  
>  This is your pencil.
>
> これはあなたのえんぴつです **か** 。  
>  Is this your pencil?

Note that all that changed was the addition of the か particle at the end.

In the case of your not-yet-a-question statement, you'll need to do the same:

> だれはしました **か** 。  
>  Who did it?

This is technically ungrammatical, so you'll need another particle here: the が
particle. This particle generally marks the direct subject of the sentence. In
this phrase, it replaces the は particle (which can be considered a "topic"
particle). Question words in question sentences are automatically the explicit
focus of the sentence, so they take the が particle instead of は, when asking a
question.

Putting it all together, then we have:

> だれ **が** しましたか。  
>  Who did it?

Now this sentence is grammatically correct. There are still more natural ways
to express this question, especially depending on the context you'd be asking
it in, but without a little more studying from your part, this is as good as
this will get.

