If you'd like to be a little polite you could say "I'd like to keep my video off please" and maybe no questions will be asked.
If you say "No camera for today" or "No video today" it will work but it will sound strange if you don't give some type of reason behind it, it will sound as if you're trying to hide something. So you could say something like : "I have no make up on so no camera for today" or "Sorry, no video today. I just woke up."
あなたが、礼儀よく言いたいのであれば、 "I'd like to keep my video off please"と言えるかもしれません。
"No camera for today" や、 "No video today"と言うと、何か理由がないとおかしに聞こえるでしょう。何かを隠そうとしてるかのように聞こえます。
だから、あなたは次のようなことを言うことができます：
"I have no make up on so no camera for today" or "Sorry, no video today. I just woke up."
1. It is quite normal for many students not to use the camera. It is simply an alternative way to conduct the lesson. In general, students do not even mention it if their camera is switched off, and teachers also, can see there is no camera for you and probably would not mention it.
"Sorry, I'm not using my camera today."
"That's OK, we'll continue without video."
2. Many student's also just say that their camera is not working. That is also an adequate explanation.
1. カメラを使わないというのは多くの生徒にとっては普通のことでしょうね。レッスンをするときの違うやりかたですね。カメラがきれていても、特に言及しない生徒もいます。教師もそうです。カメラで相手の顔がみられなくても特に言及しないかもしれません。
"Sorry, I'm not using my camera today." 今日はカメラ使わないけど、ごめんね。
"That's OK, we'll continue without video."大丈夫、カメラなしで続けよう。
2. カメラがうまく動作していない、と多くの生徒が言いますが、これも十分な説明と言えるでしょう。
I would prefer to continue the lesson with no video please
I would like to proceed with just the audio today
"I would prefer to continue the lesson with no video please"
This allows the teacher to know your what you would like for the current lesson.
The teacher will then understand that you do not want to turn your video on.
"I would like to proceed with just the audio today"
This lets the teacher know from the beginning that you would like to continue the way it is (without video)
"I would prefer to continue the lesson with no video please"
これにより、先生はあなたが今のレッスンに何を望むかを知ることができます。
先生はあなたがビデオをオンにしたくないことを理解するでしょう。
"I would like to proceed with just the audio today"
これにより、先生は最初からあなたがそれ（動画）なしで、そのままの方法を続けたいと思っていることを知ることができます。
You can send a message in the chat box before the lesson or just tell your teacher in the class, that you will do the lesson without any video, the choice is yours.
"I would prefer my video off, today!"
"I would like to do the lesson without any video!"
レッスン前にチャットボックスにメッセージを送信したり、クラスで先生に教えたりすることで、ビデオなしでレッスンを行うことができます。どのように伝えるかはあなた次第です。
例
"I would prefer my video off, today!"
今日はビデオなしが良いです。
"I would like to do the lesson without any video!"
レッスンをビデオなしでしたいです。
Having a bit of a bad hair day...So I'd like to proceed, but with my camera off please!.
Some days we might not feel we are "looking our best" !
And for any number of reasons wish to go ahead with a class..."MINUS VIDEO"
Keeping our video camera off during the lesson, is perfectly acceptable,
just as long as we communicate clearly with the teacher, our intention is to:
"proceed with the camera OFF"
時には"looking our best"(最高の顔）をしていられない日もたまにはあります。
その他色々な理由で"MINUS VIDEO"
（ビデオ無し）でレッスンを受けたい日もあります。
ただ明確に先生に
"proceed with the camera OFF"
（カメラをオフで進める）という気持ちを伝えてさえいれば、レッスン中にビデオをオフにする事は何の問題もないと思います。
Hi there, I am going to be doing today's lesson without video if that is okay.
If it is okay, I would like to continue today's class without video please.
If you would like to tell your online teacher that you prefer not to use video in your classes, you can say something like "I prefer not to use video call during my lessons if that is alright." or "Hi there, I am going to be doing today's lesson without video if that is okay.".
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