＊Please try to keep it at a reasonable volume = 常識のある音量に抑えておいてね
Reasonable = 理性的、道理をわきまえた
＊Don't party too hard = 盛り上がりすぎるなよ！
こっちだと砕けた感じで嫌味くさくないです。使い方の例としては:
Don't party too hard in the living room, I have an important meeting first thing in the morning! = 朝一で大事な会議があるからあまりリビングで盛り上がり過ぎるないでくれよ！
'Don't'の代わりに'Try not to'を使うともう少し柔らかい言い方になります。ニュアンスとしては「出来るなら」です。
I'd appreciate it if you can keep your voices down a bit.
appreciateを入れることによって、表現が「うるさくするとイヤ」から「うるさくしなかったらうれしい」と、ポジティブな聞こえになります。
keep your voices down=声を抑え気味にしてね
そこに、a bitをたすことで、「完全に静かにしてと言うつもりはないんだけど...」といった感じのやわらかさを付けられます。
アナタが注意ばかりする神経質な口うるさい人だと思われたくない場合は適当に、
"Our neighbor called the police before when we had a party at night."
「以前、夜にパーティーをしたときにご近所さんに警察を呼ばれちゃったのよ～」と、責任転換してみても人間関係がギクシャクしないかもしれませんね。
（アナタの方が前から住んでいる場合しか使えませんが。）
1. Yes, that's fine but please keep the noise down
2. OK, but please be careful with the noise
3. Great, but please don't make a disturbance
1. Keep the noise down = don't make any loud sounds
2. Be careful = be attentive
3. Disturbance = something that may bother or annoy someone
A "Why is there a police car outside?"
B "I think someone called them and said we were making a disturbance."
1. Keep the noise down = うるさい音をたてないで
2. Be careful = be attentive （気を付ける、注意を払う）
3. Disturbance = いらいらさせたり、困らせたりするもの
A "Why is there a police car outside?" なんで外に警察いるの？
B "I think someone called them and said we were making a disturbance." 多分俺たちがうるさいって誰かが警察を呼んだんだろう。
「あんまりうるさくしないでね。」とお願いする場合は、
"Do you mind keeping the noise down?"
"Would you mind keeping the noise down?"
という表現を使うことも出来ます。
"Do you mind ~?"は、少しだけ遠回しに何かをお願いする時に使います。"Would you mind ~?"は、"Do you mind ~?"より丁寧な言い方です。
ご参考になれば幸いです。
Please don't make too much noise when you friends are here
Please try to keep it down.
Please keep the noise at a minimum
When you want to politely ask your roommate to not be too loud when they have their friends over; then you can say:
-Please don't make too much noise when you friends are here.
-Please try to keep it down.
-Please keep the noise at a minimum
It would also help to explain why you want them to keep it down. For example, you can say "I have to be up very early tomorrow. I need to rest."
ルームメイトに、友達を呼ぶときは静かにしてほしい、と伝える丁寧な言い方です：
-Please don't make too much noise when your friends are here.
友達が来ているとき、あまりうるさくしないでください。
-Please try to keep it down.
出来るだけ静かにしてください。
-Please keep the noise at a minimum
出来るだけ静かにしてください。
なぜ静かにしてほしいか伝えてもいいですね：
例：
"I have to be up very early tomorrow. I need to rest."
明日は早く起きないといけないので、しっかり休みたいんです。
Have a great time, but please remember me and try to be a bit quiet
To keep it polite and friendly you can begin by asking them to have a great time and enjoy themselves. By saying 'please remember me' you are being cute, but at the same time asking them to keep it down. Using the term 'a bit quiet' is a polite and relaxed way of saying 'keep it down' as keep it down alone can sound a bit abrupt.
「良い時間を過ごして（Have a great time）」で始めると丁寧でフレンドリーな言い方になります。
「please remember me」はかわいらしい言い方ですが、同時に静かにして欲しいと頼んでいます。
「a bit quiet（ちょっと静かに）」は「keep it down（静かにする）」の丁寧でくだけた言い方です、「keep it down」だけだと少しぶっきらぼうな感じになることがあります。
Can you make sure to keep your voices down tonight?
I need to have some quiet to concentrate can you keep the noise at a reasonable level?
Please don't be too loud, I really need to concentrate.
A good rule to follow is to always say please when asking for something, then follow up with a thank you. For example ,"Please don't be too loud, I really need to concentrate." (Their response). "Thank you for being considerate." This is a great way to be polite and show appreciation for them doing what you asked!
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