ことにする with causative


> 私は子供に、自分のことは自分でさせる **ことにし** ている。
>
> 10時に駅で待ち合わせるという **ことにし** ませんか。

So in both the two sentences above, the causative form is used. Is this
because the person speaking is talking to an inferior and giving orders? What
would be accurate translations?

> 2週目に3日ぐらい出張する **ことになる** だろうと思います。

In this one, I don’t really understand why they use ことになる instead of ことになった.
Wasn’t the decision that the person would be going on a business trip already
decided in the past?

Thank you very much for your kind input.




`dictionary-form + ことにする` means "to decide to ～", and `dictionary-form +
～ことにしている` means "I always ～", "It's my policy to ～", "I make a habit of ～ing",
etc.

>   * 私は子供に、自分のことは自分でさせることにしている。  
>  It's my policy to make my child take care of himself. (lit. "make my child
> do his own things")
>   * 10時に駅で待ち合わせるということにしませんか。  
>  Shall (we) meet at the station at 10 o'clock then?
>

More examples here: <https://www.renshuu.org/grammar/90>

させる in the first sentence is a causative form, but it's not directly related
to the ことにする construction. There is no causative form in the second sentence.

`dictionary-form + ことになる` means "it is determined/decided/arranged that ～",
"to be going to ～" (due to some external cause out of the speaker's control),
"to end up ～ing", etc.

>   * 2週目に3日ぐらい出張することになるだろうと思います。  
>  I think I'm (probably) going to make a business trip for a couple of days
> on the second week.
>

Note that he is just guessing his future. His business trip is not fixed yet,
although he thinks it's very likely.

