1回につき、これを２つ飲んでくださいと
薬を指しながら説明する場合は
Take two of these at the same time.
とtheseの時に薬を指して説明すればわかりやすいと思います。
もしくは錠剤を2個という意味の
Take two pills at the same time.
毎回薬を飲むとき2錠飲んでください。
Take two pills every time you take the medicine.
などの言い方もあります。
ご参考になれば幸いです。
You can just ask the person to take two at a time, or take two 'at once'. Saying 'please' makes the phrase more polite, so this may depend on who you are speaking to. We are often more polite to people we don't know well. You can go on to give more specific details like in the last sentence, by saying how many times a day to take the two pills.
take two at a time' あるいは 'take two at once' と言えます。
'please' を使うとより丁寧になります。誰に対して話しているかによるでしょう。よく知らない人には丁寧に伝えることが多いです。
最後の例のようにより詳しく、一日何回飲むかを伝えることもできます。
"Dosage" is the size or amount that needs to be taken each time when taking medication or supplements.
If it is indicated to take something, this instructs the person to consume the medication. These instructions indicate that while drinking a full glass of water, the person needs to consume two pills.
The term "at a time" indicates that two pills are to be used simultaneously. Simultanous= the same time.
"Dosage" は薬やサプリメントの一度に取る量をいいます。
"To take" は「薬を飲む」という意味です。ここでは、グラス1杯のお水で薬を2錠飲むよう伝えています（→例2）。
"At a time" は、薬2錠を "simultaneously"（同時）に飲まなければならないことを表します。
Simultaneous = the same time（同時に）
You should drink two pills every time until the end of this month.
All three response can be used to explain the dosage and time that one should take their medicine tablets. Each time one needs to take 2 pills at a time. The first response one needs to take it once daily, the second response is three times daily, and the last is until the end of the month.
The dosage for this medicine is two tablets/pills at a time.
Take two tabs at a time
"The dosage for this medicine is two tablets/pills at a time."
"Take two tabs at a time"
Both of these expressions can be used to accomplish what you are trying to say. The first one is a more formal way of saying it. I assume you are a doctor/pharmacist/pharm tech/ so you really want to be professional when telling this to someone, so the first expression is the most appropriate. The second expression is less formal and can be used with people that are close to you such as family and friends when they ask you for medical advice.
"The dosage for this medicine is two tablets/pills at a time."
"Take two tabs at a time"
（1回につき2錠飲んでください）
どちらの表現でもあなたの言いたいことを伝えられます。
一つ目の例はよりフォーマルな言い方です。たぶんあなたは医者か薬剤師さんなのでしょう。ですから、プロフェッショナルな言い方をする必要がありますね。なので、一つ目の例が最も適切です。
二つ目の例はよりインフォーマルです。これは、家族や友達など親しい人にアドバイスを求められたときに使えます。
You should take two tablets at the same time daily.
By saying "you should," it is a little more polite so that it doesn't sound like you're forcing the patient to do anything. If you tell the patient to "take two tablets at the same time" it means that they will be consuming two tablets. I hope that this helps. :)
"you should" と言うと命令している感じにならず、少し丁寧になります。
"take two tablets at the same time" は「薬を2錠飲む」という意味です。
参考になれば幸いです。
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