"Impossible"
"Unbelievable"
"Impractical"
The above are all synonyms of "unrealistic" which means the advice which was given to you is not showing you things as it is in real life. It is based on what is wanted or hoped for rather than on what is possible."Impractical" not seeing things as they really are. "Unbelievable" is not being able to believe something because it is too far-fetched.
「現実的ではない」は直訳的には
That is not realistic. / That is unrealistic.
「それは現実出来ではない」
という表現もできますが、ここでは状況的に「効き目がない・効果がない」ということを伝えたいことと思いますので、
I don't think that will work (for me).
「そんなの（僕には）[上手くいく](https://eikaiwa.dmm.com/uknow/questions/43892/)・[効果がある](https://eikaiwa.dmm.com/uknow/questions/78474/)とは思えないな」
という表現をご紹介します。
薬などの「効果がある」や「（薬が）効く」はworkという動詞を使うことができます。
No. I don't believe it. It won't work.
「いやいや、そんなの信じられないね。効かないよ」
こんな言い方も良いと思います。
ご参考になれば幸いです。
If something is unrealistic it can also be described as "unfeasible". This is commonly used in business conversations to say when something is not possible.
If the advice is not practical and completely out of touch with reality, then this can be described as having unrealistic expectations on the situation at hand. This is good to use if you feel people to need to adjust their perspective on an issue or problem.
Example sentences
- I find what she said to be highly doubtful.
- Well I believe that to be scarcely credible, where did you get your information from?
- That is beyond belief, where are you getting your information from?
例文：
- I find what she said to be highly doubtful.
（彼女の言ったことは本当とは思えない）
- Well I believe that to be scarcely credible, where did you get your information from?
（それはちょっと信じられない。どこの情報なの？）
- That is beyond belief, where are you getting your information from?
（それは信じられない。どこの情報なの？）
- That deadline is unachievable within the set time frame.
- Aiming too high can lead to disappointment in the long run.
- Your advice is giving me false hope.
The answers above are three alternatives to the phrase "That's unrealistic".
"Unachievable" is another way of saying that something is impossible or that a demand cannot be met.
"Aiming too high" is for example when a person may aspire to be someone great or famous, however that individual may not be talented enough to reach the goal they have set themselves. In this instance that person would be "aiming too high".
You are giving someone "false hope" in a situation where you may give them advice which protects their feelings, comforts them or just to make them feel better.
- That deadline is unachievable within the set time frame.
決められた期間で締め切りに間に合わせるのは不可能です。
- Aiming too high can lead to disappointment in the long run.
長い目でみると、高望みしすぎると失望してしまうかもしれません。
- Your advice is giving me false hope.
あなたのくれるアドバイスは私をぬか喜びさせるだけです。
上記はどれも"That's unrealistic."（非現実的です）というフレーズを言い換えたものです。
unachievable＝～に手が届かない。需要にこたえられない。
aiming too high＝～が不可能。例えば、ある人が有名人になろうと考えていたとしても、特別なタレントもなくその夢を叶えることは不可能である、というとき使います。
false hope＝偽りの期待。もしあなたのアドバイスが相手の気持ちを守ったり、慰めたり、気分を良くするだけの場合、相手をぬか喜びをさせている場合もあるかもしれません。
Maybe sometimes telling people that you don't like the advice they have given can sound a little rude, so you can soften it by adding "I'm sorry but ....", "Pardon me for saying but ....", or "That's an interesting suggestion but..."
助言が気に入らなかったとき人に伝えると、少し失礼に聞こえてしまう時がありますので、以下を付け足して柔らかい表現にすることが可能です。
I'm sorry but ...., すみませんが、
Pardon me for saying but ...., こんな事言って失礼ですが、
That's an interesting suggestion but...興味深い提案ですが、
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