やら

I wonder..., who knows..., so-called, what they call, and...

particle Uncommon #12,816
I wonder..., who knows... Often follows a question word in an expression of uncertainty or bewilderment.
JA: どこに置いたらよいのやら。
EN: I wonder where I should put this.
so-called, what they call Often used after と to express distance or uncertainty about a name or description.
JA: 彼の夢とやらを聞かせてください。
EN: Tell me about this dream of his, or whatever you call it.
and..., and... Can be repeated to list examples, often suggesting there are various things of that kind.
JA: 風やら雨やらで、試合は中止になった。
EN: The game was canceled because of wind and rain and all that.

いつ戻れるやら…

Who knows when I’ll be able to get back…

— 灼熱の魂 (2010)

では話とやらを聞かせてもらおうか

Well then, let’s hear what you have to say.

— M - Eine Stadt sucht einen Mörder (1931)

何のことやら

I have no idea what you're talking about.

— どん底作家の人生に幸あれ! (2019)

何を言い出すやら

What on earth are you talking about?

— 最強のふたり (2011)

どこに行けばよいのやら。

I wonder where I should go.

風やら雨やらで、我々の散歩は台無しだった。

The wind and rain ruined our walk.

本のすみになにやら書き込んである。

Someone has scribbled something in the corner of the book.

私はなにやら彼に話さなければならないことがある。

There’s something or other I need to talk to him about.

いったい何のことやら

I have no idea what you're talking about.

— かぐや姫の物語 (2013)

どうなることやら心配だね

I'm worried about how things will turn out.

— 魔女の宅急便 (1989)

避難計画とやらできたん?

So, did you ever finish that evacuation plan?

— 君の名は。 (2016)

これはどこに置いたらよいのやら。

I have no idea where to put this.

何から話せば良いことやら

I don't even know where to begin.

— ロード・オブ・ザ・リング (2001)

何を言ってるのやら?

What are you talking about?

もう何が何やら

I don't know what's what anymore.

— デッド・ドント・ダイ (2019)

でもいつのことやら

But who knows when that will be.

— ベルリン・天使の詩 (1987)