Usage of よう without に particle


みなさん、こんにちは！

So, I am a beginner. I have just started reading my first manga in Japanese,
鬼滅の刃, and I've encountered a sentence which I don't really understand the
grammar for. Here it is:

> 丸腰{まるごし}​であるのを悟{さと}られないよう振{ふ}りかぶった体勢{たいせい}で手元{てもと}を隠{かく}す

I've understood it to mean roughly:

> He hid his grip so that I would not realize that he was unarmed.

which makes sense in context. The grammar that confuses me is the usage of
「よう」 without any particle afterwards. I am familiar with 「ように」 and 「ような」 but I
am not quite sure if I am missing something here.

Was 「に」 simply omitted in the sentence above? If that is the case, is such
usage common or is it a more dated style?

Here's the page in question with some extra dialog:
<https://i.stack.imgur.com/GhSR9.jpg>




> 「Phrase A + よう + Phrase B」
>
> 「Phrase A + ように + Phrase B」

In basic meaning, the two patterns above are identical.

The only difference is that the second one using 「ように」 is **more casual and
conversational** than the first with 「よう」. For that reason, 「よう」 tends to be
used more often in writing.

The sentence you have quoted sounds non-conversational; therefore, 「よう」 fits
better there.

「よう **な** 」, BTW, is **not** an option here as it needs to be followed by a
**noun**.

「よう」 and 「ように」 are followed by **verb or adjective phrases** (or whole mini-
sentences).




> 「Phrase A + よう + Phrase B」
>
> 「Phrase A + ように + Phrase B」

In basic meaning, the two patterns above are identical.

The only difference is that the second one using 「ように」 is **more casual and
conversational** than the first with 「よう」. For that reason, 「よう」 tends to be
used more often in writing.

The sentence you have quoted sounds non-conversational; therefore, 「よう」 fits
better there.

「よう **な** 」, BTW, is **not** an option here as it needs to be followed by a
**noun**.

「よう」 and 「ように」 are followed by **verb or adjective phrases** (or whole mini-
sentences).

