All of these phrases are asking for the doctors opinion, the first asks his/her personal opinion, if there were in your shoes.
Second, asking which would be best for you individually.
Lastly, asking which one would work the fastest and has the biggest effect.
Amongst these options which one would you recommend?
*Which treatment do you think is the best? - Good, better,best (Superlatives). Given options to choose from if you want something that is extremely good , you say best. Other examples of superlatives: low lower lowest, tall taller tallest.
Example Sentences:
Joe's restaurant serves the best burger in town.
I think chemotherapy would be the best treatment for you.
*Amongst these options which one would you recommend? - When comparing more than two items use amongst and a comparison of two items only, use between.
Example Sentences:
Amongst the four of us whom do you think is the best cook?
If I was to choose between Marketing and Accounting, I would go for Accounting.
例文
*Which treatment do you think is the best?
どの治療法が一番良いと思いますか？
good良い、betterより良い、best一番良い（最上級）。与えられた選択肢からとても良いものを望むのであれば、best（一番良い）と言います。他の最上級の例はlow lower lowest, tall taller tallest.です。
例文
Joe's restaurant serves the best burger in town.
町でジョンのレストランが一番美味しいハンバーガーを出す
I think chemotherapy would be the best treatment for you.
化学療法があなたにとって一番良い治療法だと思う
例文
*Amongst these options which one would you recommend?
これらの選択肢の中で、どの治療法が良いと思いますか？
2つ以上の物を選ぶ時に amongst を使い、2つの物だけを比べる時は betweenを使います。
例文
Amongst the four of us whom do you think is the best cook?
私達4人の中で誰が料理が一番上手だと思う？
If I was to choose between Marketing and Accounting, I would go for Accounting.
マーケティングと経理のどちらかを選ぶのであれば、経理にするよ。
Explanation: The doctor will advise what is best for you. You may ask him to recommend the best treatment in your case.
Example sentence:
"I recommend that you take a short course of physiotherapy, along with your usual medication."
説明: 医者があなたにとってベストが何かをアドバイスするでしょう。あなたの症状の場合の最善の治療を聞きましょう。
例文:
"I recommend that you take a short course of physiotherapy, along with your usual medication."
（通常の投薬に加え、理学療法の短いコースを受けることをお薦めします。）
"What is your professional opinion?" Here you are just asking them what they think, according to their knowledge and experience (professional opinion) is.
"Which is the best option according to you?" This is a more of an either or question. Like which option would they choose. According here just means, in correlation or based on their opinion.
"What is your professional opinion?"（あなたの専門家としての意見を聞かせてください）
- ここでは、「あなたの知識と経験を基に意見を聞かせてください」とお願いしています。
"Which is the best option according to you?"（あなたはどの選択肢が最も良いと思いますか）
- これは選択肢の中から選んでもらっています。あなたならどれを選びますかのような感じです。"According" はここでは「あなたの考えでは［に基づくと］」という意味です。
A) What would you recommend ?
When asking someone what they would recommend you are asking them indirectly what they would choose. Eg :
Which dish would you recommend ?
What color would you recommend ?
B) What do you think would be best ?
Here you are asking someone what would be the best option (good ,better, best.) , the greatest option . eg
What shoe do you think looks best ?
What house do you think is the best ?
C) Which treatment will be the best ?
These are all possible ways you would state your questions, some are direct ways of asking and some are indirect. I hope this will help you!
A) What would you recommend ?（勧めるとしたらどちらですか）
「あなただったらどちらを選びますか」と尋ねています。
例：
Which dish would you recommend ?（どの料理がおすすめですか）
What color would you recommend ?（どの色がおすすめですか）
B) What do you think would be best ?（何がベストだと思いますか）
ここでは、ベストな選択は何かと尋ねています。
例：
What shoe do you think looks best ?（どの靴が一番良いと思いますか）
What house do you think is the best ?（どの家が一番良いと思いますか）
C) Which treatment will be the best ?（どの治療がベストですか）
これらはどれもこの状況で使える言い方です。直接的に尋ねているものもあれば、間接的なものもあります。
参考になれば幸いです！
When your not sure what to do for the best then you might ask someones opinion you can do this by saying 'what one do you receommend?' or 'what one would you suggest?'
by saying 'what one would you choose?' this is asking their personal opinion and what one they would do
最良の選択が何か分からないときには、人の意見が聞きたくなるかもしれません。
それは次のように聞けます。
'what one do you receommend?'
'what one would you suggest?'
（あなたはどれを勧めますか）
'what one would you choose?'（あなたならどれを選びますか）では「あなたならどうするか」と相手の個人的な意見を尋ねています。
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