I went to the hospital, but it was closed for a National Holiday.
"I went to the hospital, but it was closed for a National Holiday."
Closed - Not open to patients, visitors, etc.
For - Meaning because of or for a specific purpose. The reason or purpose here is a national Holiday.
例文
"I went to the hospital, but it was closed for a National Holiday."
（病院に行ったけど、祝日で閉まっていた）
Closed - 患者、訪問者などが入れない
For -〔理由・目的を表す〕～のために、～のせいで ※ この場合は「祝日」が理由です。
I went to the hospital but it wasn't opened because it was a national holiday.
"I went to the hospital but it wasn't opened because it was a national holiday."
'It wasn't opened' is the same as 'closed'. You can also say 'government holiday' or use the name of the holiday to explain it further. (I went to the hospital but it wasn't opened because it was Thanks Giving).
"I went to the hospital but it wasn't opened because it was a national holiday."
［訳］病院に行ったけど、祝日だったので閉まっていました
'It wasn't opened'とは'closed'（閉まっていた）と同じ意味です。
また、'government holiday'や祝日の名前を言うこともできます。例えば：
"I went to the hospital but it wasn't opened because it was Thanks Giving."
［訳］病院に行ったけど、サンクスギビングだったので閉まっていました
I went to the hospital but it was closed due to a national holiday.
The phrase "due to" is another way to say "because of." You can use the phrase "national holiday" in both British and American English. I hope that this helps. :)
I went to the hospital, but it was closed due to a national holiday.
If you want to explain that the hospital was closed because it was a national holiday, you can say:
"I went to the hospital, but it was closed due to a national holiday."
「祝日だったため病院が休みだった」は次のように言えます。
"I went to the hospital, but it was closed due to a national holiday."
（病院に行ったけど、祝日だったので休みだった）
I went to the hospital but it was close because it was a public holiday
I was at the hospital but it was closed when I got there because it was a national/public holiday
When you want to explain that you went to the hospital but found out that it was closed because of the national holiday on the day you went; then you may explain this in the following ways:
-I went to the hospital but it was close because it was a public holiday
-I was at the hospital but it was closed when I got there because it was a national/public holiday
「病院に行ったけど祝日で休みだった」は、次のように言えます。
-I went to the hospital but it was close because it was a public holiday
（病院に行ったけど祝日で休みだった）
-I was at the hospital but it was closed when I got there because it was a national/public holiday
（病院に行ったけど祝日で休みだった）
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