How do you use 〜と知る?

Question

I've often seen and heard the expression 〜と知る（知っている）. When I think about it, it makes sense in the context of the quoatation-と, like with 〜と言う or 〜と思う. It seems like it means "Know that 〜".

ミユキちゃんが結婚したと知ってる？　→　Did you know that Mikyuki got married?

However, the few times I've tried to use it, I was told I was using it incorrectly, and that I should instead use 〜こと／のを知る.

ミユキちゃんが結婚したこと／のを知ってる？

So what are the rules for using 〜と知る? Do 〜と知る and 〜こと／のを知る have different meanings and rules (they seem the same to me)?

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Update: I've found quite a few examples from my Bible. It's the 新共同訳 version, and I was able to search it here. I searched for ～と知る, ～と知って, and ～と知った. Here are a couple examples:

• 「群衆は、イエスも弟子たちもそこにいないと知ると、自分たちもそれらの小舟に乗り、イエスを捜し求めてカファルナウムに来た。」　－　ヨハネによる福音書 / 6章 24節
• 「けれども、人は律法【りっぽう】の実行ではなく、ただイエス・キリストへの信仰によって義とされると知って、わたしたちもキリスト・イエスを信じました」　－　ガラテヤの信徒への手紙 / 2章 16節
• 「ヨナタンは言った。『そのような事は決してない。父があなたに危害を加える決心をしていると知ったら、必ずあなたに教えよう。』」　－　サムエル記上 / 20章 9節

Answer 1

The examples are very interesting. It looks like, whenever と知る can be used, it means "find out" rather than "know". Another way to say this is, whenever と知る can be used, you can replace the verb with 分かる. With "find out", you cannot have duration, in other words, you can say:

I knew that theorem for two days, (but I forgot it).

but you cannot say

* I found out that theorem for two days.

the aspectuality matters. Applying this to Japanese, you can use と知る with a simple tense (under which 知る means "find out"):

風の知らせで、みゆきちゃんが結婚したと知った。

but not with perfect (under which 知る means "know"):

* 昨日から、みゆきちゃんが結婚したと知っている。

And indeed this makes sense because と (similar to "to") implies the goal of change of location/state of something. Finding out something is a change of state, but knowing something is not.

Answer 2

ミユキちゃんが結婚したと知ってる？

This sentence is grammatically correct but not natural.

ミユキちゃんが結婚したって知ってる？

This one is natural. In modern Japanese conversation, it does 促音便化 in this case. But, the old style is also still in use even in conversation.

ミユキちゃんが結婚したと知らされた。

So, here is the problem. "知ってる?" is quite informal, but "したと" is quite formal. That difference makes us uncomfortable.