I can't do anything
私は何もできない
I can't do anything about it
(状況に対して)私は何もできない
その状況ですと
I can't do anything (about it) because I don't know how to deal with the problem.
問題に対してどのように対処していいかわからないので、私には何もできません。
と付け加えてもいいかもしれません。
The most common ways to say it is :
"Sorry, I could not solve the problem."
"I am sorry but I could not fix it."
"There is nothing I could do about it."
"Unfortunately, there was nothing I could do."
"I tried, but I couldn't solve it."
"It is out of my hands."
Sorry (apologizing) It is polite to apologize in such a situation.
この表現として一般的なものは下記になります。
"Sorry, I could not solve the problem."（問題を解決することができずすみません。）
"I am sorry but I could not fix it."（問題を解決することができずすみません。）
"There is nothing I could do about it."（私にできることはなさそうです。）
"Unfortunately, there was nothing I could do."（残念ですが、私にできることはありませんでした。）
"I tried, but I couldn't solve it."（やってみましたが、問題の解決はできませんでした。）
"It is out of my hands."（私の手に負えません。）
Sorryと言って謝ることが礼儀正しいでしょう。
1. There was nothing I could do about the situation.
状況について私ができることは何もありませんでした。
2. This is out of my control.
これは私のコントロール外です。
The word "control" means the power to influence or direct people's behaviour or the course of
events. Therefore if something is out of your control, it means that you do not have the power to
influence people's behaviour or the course of events.
1. There was nothing I could do about the situation.
（状況について私にできることは何もありませんでした）
2. This is out of my control.
（これは私のコントロール外です）
単語"control"は、人の行動や出来事の過程に影響を与えたり指示したりする権限という意味です。よって、何かがout of your controlだというのは、人の行動や出来事の過程に影響力を持たないという意味です。
There was nothing else I could do to fix the problem.
"There was nothing else I could do to fix the problem." this means that you could not do anything to fix the problem.
"There was nothing else I could do to fix the problem." this means that you could not do anything to fix the problem.
「問題を解決するために、他にできることは何もなかった。」為す術がなかったことを意味します。
It was out of my hands. - "to have your hand (in something)" means that you had some power or influence over that thing; if "(something) is out of your hands," this means that you don't have any power or influence over it.
例文
It was out of my hands.
それは手におえなかった。
"to have your hand (in something)"
～を手中に収める
物事に力や影響力を持つことです。out of your handsは、物事に対して力や影響力がないということです。
I am so sorry, but I was helpless in that situation...
Being "Helpless" is an awful feeling...There is nothing to be done. Nowhere to turn.
No options at all ;-(
"I am so sorry, but I was helpless in that situation..."
"helpless"はどうすることもできない、無力なという意味で、その状況に陥ると辛いですね。
"There is nothing to be done. Nowhere to turn." （できることもなければ、頼る人もいない。）
"I am so sorry, but I was helpless in that situation..." （本当にすみません、しかしあの状況では私はどうすることもできませんでした。）
I'm afraid I don't know how to deal with this problem/issue.
I'm sorry, I don't know how to attend to this issue.
I cannot sort out this issue, sorry.
If you want to apologize to someone in a polite way, you can use the following phrase:
''I'm afraid...''
The phrases ''deal with'' , ''sort out'' and ''attend to'' are similar. They mean that you cannot do
something.
We can either use the verbs, "to fix," or, to deal with," to talk about working on a solution to a problem. We can also mention that, "there was nothing I could do," to mention that we didn't have the capable to fix or deal with the problem/issue.
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