Your lessons are so popular I can't make a booking.
Your lessons are so popular, there are no available slots in your schedule.
Your lessons are so popular I can't make a booking.
先生のレッスンは人気があるから予約できません。
Your lessons are so popular, there are no available slots in your schedule.
先生のレッスンは人気があるからレッスンのスケジュールに空きがないです。
是非使ってみてください！
When I try to book you, all your lessons are taken!
I would like to have more lessons with you, but competition for your slots is very keen
You have a favourite teacher, but it is so difficult to actually book one of her lessons!
She opens lessons once a day and they are gone like hot cakes! You say to your teacher:
"When I try to book you, all your lessons are taken!"
"So sorry, I hope you are lucky next time!"
To go like hot cakes = If things go like hot cakes, they are consumed, or used or sold very quickly.
"The salesman says they've been going like hot cakes."
あなたはお気に入りの先生がいますが、実際彼女のレッスンを予約するのは困難です。
彼女は一日に一回レッスンをオープンしますが、それらは "gone like hot cakes" です（あっと言う間に予約は埋まってしまします）。
あなたは先生に次のようにいうことが出来ます。
"When I try to book you, all your lessons are taken!"
（先生のレッスンを予約しようとしても、あなたのレッスンはいつもいっぱいです）
"So sorry, I hope you are lucky next time!"
（ごめんなさい、次回は運がいいといいですね）
To go like hot cakes = 熱いホットケーキは飛ぶように売れるので、すぐにどんどん売れるという意味になります。
"The salesman says they've been going like hot cakes."
（それらは飛ぶように売れているとセールスマンは言います）
You're so popular that your classes are all booked!
Your classes are so in demand, it's hard to find an opening!
you can say that the teacher's classes are popular or "in demand" or "high in demand" (this is an economic term)
find an opening = to find a lesson slot that is open / to find an opportunity
次のように表現することが出来ます。
その先生のクラスは"popular "(人気がある）又は、"in demand" や "high in demand" (これは経済用語で需要があると言う意味です）
find an opening = 空きを探す、ここではレッスンの空を探す
It is difficult for me to book your lessons because you are so popular.
I am finding it hard to book your lessons, probably because you are so popular.
It is difficult for me to book your lessons because you are so popular.- this is a good way of saying that you are having problems (it is difficult) booking a lesson with your teacher. If your opinion is that your teacher is very popular and that is why you are having problems booking a lesson, then you can say, 'because you are so popular.' To be popular means that people like you a lot and therefore want to 'be with you', 'talk to you' or just 'hang out with you'.
I am finding it hard to book your lessons, probably because you are so popular.- 'I am finding it hard to book your lessons' is another way of saying 'It is difficult for me to book your lessons'. To 'find something hard/difficult' is when it is NOT easy to do something. Example- 'I am finding it hard to ride this bike. It is not easy!'
It is difficult for me to book your lessons because you are so popular.
（あなたのレッスンは人気があるので、予約が取れません）
これは、その先生の予約が取りにくいという事を言い表すのによい表現です。
その先生は人気があるので予約が取りにくいとあなたが思うなら 'because you are so popular.' と言う事が出来ます。
"To be popular"とは多くの人が好きで、一緒にいたかったり、話がしたいという意味です。
I am finding it hard to book your lessons, probably because you are so popular.
（あなたは人気があるので、レッスン予約が取りにくいと思います）
'I am finding it hard to book your lessons'とは 'It is difficult for me to book your lessons'（あなたのレッスンは予約が取りにくい）のもう一つの言い方です。
'find something hard/difficult' とは、簡単にできないという意味です。
例
'I am finding it hard to ride this bike. It is not easy!'
（自転車に乗るのは難しいです。簡単な事じゃないです）
Your lessons are always booked since you've got high ratings.
"Your lessons are very popular." This is a common way of expressing that a lot of people like your teacher, and so their lessons are super popular.
"Your lessons are always booked since you've got high ratings." Here you express why their lessons are always full (booked) as they have very good ratings (a way people express that they like them).
"Your lessons are very popular."（あなたのレッスンはとても人気があります）
- これは、その先生がたくさんの人に好かれていて、レッスンがすごく人気であることを一般的な言い方で伝えています。
"Your lessons are always booked since you've got high ratings."（あなたは評価が高いので、レッスンがいつも予約で埋まっています）
- ここでは、レッスンがいつも予約で埋まっている理由を伝えています。とても評価が高いということです。
Ratings = 評価
How can I book you? Each time I try there are no available slots
Asking the teacher directly how to book them will help, as they may be able to reserve a specific time for you on a particular day. It is better than asking a vague question such as "do you have a busy schedule?"
先生に直接「どうしたらあなたのレッスンを予約できますか」と尋ねることができます。
特定の日の特定の時間を用意してくれるかもしれません。"do you have a busy schedule?"（仕事は忙しいですか）といった曖昧な質問よりも良いです。
It's hard to book your lessons as you are so popular
Your lessons are so popular it's difficult to book one
If a tutor is popular then many student's will book lessons so you might find it hard to book one
If something is hard to do you can also use the term 'difficult'
Popular means liked by many people
I struggle to book your classes due to your popularity.
You are so popular its hard to book a class!
"I struggle to book your classes due to your popularity." 'Struggle' is a term to describe something hard or exhausting. 'popularity' is the term used for being popular 'School is a popularity contest'
"I struggle to book your classes due to your popularity."（あなたの人気があるので授業をなかなか授業を予約できません）
= 'Struggle' は難しいことや骨の折れることを表します。'popularity' は「人気」の意味です。
例：
'School is a popularity contest'（学校は人気コンテストのようなもの）
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