The correct usage of ～と決める, ～に決める, and ～を決める


Browsing the example of
[決める](http://tangorin.com/examples/%E6%B1%BA%E3%82%81%E3%82%8B), I found at
least there are 3 patterns as follows:

  * 行く **と** 決めた。I decided to go.

  * 行くまい **と** 決めた。I decided not to go.

  * 車を買うこと **に** 決めた。I decided to buy a car.

  * 会議の日 **を** 決めた。I decided the meeting date.

# Questions

  * Are my conclusions below correct?

    * ～に決める can only follow こと.
    * ～と決める can only follow verb in dictionary form.
    * ～を決める can follow any noun.
  * Which is the correct interpretation of「私たちは、会議の日を三月四日に決めた。」?

    * We decided the meeting date to be March 4.

    * We decided the meeting date on March 4. (But the meeting date is unspecified)




**1.** Basically you follow the next template:

> (the thing/subject the decision is assigned to, i.e. the direct object) +
> **を** (what was decided to be) + **に/と** + 決めた

Based on this, we can also see this pattern:

> (constant) + **を** (variable) + **に/と** + 決めた

  * **を** is used to unite a transitive verb such as 決める with its direct object. It answers the question "What is subject to decision?".

  * **に** among other uses marks a direction (we often use **" to"** as a translation); this direction can also point to intangible things like ideas or decisions, for example:

> 朝食をホットケーキに決めました。
>
> **More natural translation** : I decided to eat hotcakes as breakfast.
>
> **More literal translation** : I decided breakfast **to (be)** hotcakes.

We can then say **に** it will answer the question "What is the decision?".

  * Now the use of **と** instead of に in the formula is tricky, it implies the subtlety of something **" arriving to its final state"**. It will also answer "What is the decision?" but with a definitive tone.

We can see this behaviour as well with the verb **なる** in **に + なる** and **と +
なる** :

> やっと先生 **に** なりました！
>
> I finally became a teacher!
>
> やっと先生 **と** なりました！
>
> I finally became a teacher! **(Implying the speaker sees becoming a teacher
> as some sort of final stage, maybe it finally got a degree for becoming so
> after a long time and can finally begin to work).**

**2.** Think about the above and you'll find the answer to your questions:

> Are my conclusions below correct?
>
> ～に決める can only follow こと.
>
> ～と決める can only follow verb in dictionary form.
>
> ～を決める can follow any noun.

Answer is none of those conclusions is correct, the summarised pattern is as
follows:

> **noun** + **を** + **noun** * + **に/と** + 決めた

* **Note** : The second noun of the formula may not be a noun per se but a verb or even an adjective put in a "noun-form" with the help of things like こと, 連用形, 連体形 etc...

> Which is the correct interpretation of 「私たちは、会議の日を三月四日に決めた。」?

The first one, following the patterns I showed you we can see that the meeting
date was the subject being put to decision and that March 4 is the decision
outcome.

