There was hair in the bathtub and the room was really dusty.
Could you have someone thoroughly clean the room please?
英訳１：「まだあちこちに髪の毛やほこりがあります」という文です。
「どこ」とは言わずに、「あちらこちらに」と言うときは、everywhereなどが適当です。
英訳２：「バスタブに髪の毛があったし、部屋もかなりほこりっぽかった」という文です。
dustは「ほこり」ですが、dustyなら「ほこりっぽい」という形容詞です。
英訳３：「どなかたに部屋を完ぺきにきれいにしていただけますか？」という文です。
Could you ...?は「…してもらえますか？」という丁寧な依頼の表現。
thoroughlyは「完全に、とことん」という意味の副詞です。
This room has not been properly cleaned, and I am very dissatisfied.
Housekeeping did a poor cleaning job because there is still hair in the tub and dust all over.
I would like a refund on my room because it is not cleaned properly, and I am not staying in it.
"Properly cleaned" is a way to imply that something is completely clean or thoroughly cleaned. It is reasonable for a hotel guest to require a room to be properly cleaned, so the hotel should understand any disappointment if this is not the case. It would be reasonable to make a complaint to the hotel manager and express that one is unhappy or "dissatisfied."
If something has not been completed as expected or as required, it means it was a "poor" or bad quality job. Another expression meaning the same thing is, "this job was poorly done."
Requesting a refund for not getting what one paid for is the usual way to deal with a product or service that was not provided per one's reasonable expectations. It is necessary to explain why the product or service is not up to standard. In this case, it would be because there is hair remaining in the bathtub and dust everywhere.
"properly cleaned" は、それが完全にきれいなこと、あるいはきちんと掃除されていることを表します。宿泊客がきれいな部屋を求めるのは当たり前のことなので、それができていないならホテルもその失望を理解してくれるはずです。ホテルの支配人に不満（＝dissatisfied）を伝えるのはもっともなことです。
仕事が求められているレベルに達していなければ、それは "a poor job" あるいは "a bad quality job" と表せます。同じ意味の別の言い方は "this job was poorly done." です。
商品やサービスが当然求められる水準に達していないときには、返金（＝refund）を求めるのが一般的です。なぜその商品・サービスに不満があるのか理由を伝える必要があります。この場合は、髪の毛がバスタブに残っていたり、ほこりが目立つということです。
The best way to refer to this is "filth" or "filthy". When something is Filthy it means that it is unclean. More over, it means that it is unclean and it should be clean.
I checked in my room today and the bath tub was filthy.
I called the front desk and told them to come clean my room.
I was not happy that my room was untidy.
Filth - disgusting dirt.
これについて表すベストな表現は "filth" または "filthy" です。
"filthy" は「汚い」「きれいであるはずのものが汚い」という意味です。
I checked in my room today and the bath tub was filthy.（今日チェックインしたら、バスタブが汚れていました）
I called the front desk and told them to come clean my room.（フロントに電話をして、部屋を掃除するように言いました）
I was not happy that my room was untidy.（部屋が片付いていなくて残念でした）
Filth - 不快な汚れ
My room isn't clean. There is dust all over and hair in the bathroom.
When making a complaint like this, it is important to be specific so that the staff is able to fix the problem. I would start by stating that the room is not clean and then explain the ways in which the room isn't clean so that the staff can solve the problem. I hope that this helps. :)
This room has not been cleaned properly. There's hair in the bath and the room has not been dusted.
If you are not in North America, it's usual to say "bath" instead of "tub". "Tub" is American English, and "bath" is British English. Hotel staff in Europe are more likely to speak and understand British English than American English. If you are visiting a former British colony such as Australia or India and you know the British English word or phrase, it’s better to use that.
My room is disgusting! There is hair in the tub and dust everywhere.
The cleanliness of my room is unacceptable. There is hair in the tub and dust everywhere.
I find my room unacceptable. There is hair in the tub and dust everyhere.
All three of these responses will communicate your problem to the hotel management. The first response is more aggressive and confrontational.
The second two responses are softer but due express displeasure. All three of the sentences should get management's attention quickly.
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