These would be great responses to your online teacher's greeting.
A simple "thank you" is enough, actually. But I think "Thanks. How are you?" is the best choice because that helps to start a natural conversation!
これらはオンラインの講師のあいさつに対する返事としてとてもいいです。
シンプルに Thank you. と言えば、実際は十分です。でも、Thanks. How are you? と言うと自然な会話が始められるので、これがいちばんです！
Thank you, I'm very excited/happy to take your class
"Thank you, I'm very excited/happy to take your class" - Your teacher will appreciate knowing that you are happy or excited to take his/her class. Also you could say something like "Thanks, glad to be here"
Thank you, I'm very excited/happy to take your class.ということで、あなたが授業に満足していると知って、先生も嬉しいと感じます。
Thanks, glad to be here.ということもできますね。
1.Thank you. I am happy to be here.
- This is a polite way to inform the teacher that you glad to be in their class.
2.Thank you. How are you?
- This is a way you can then greet the teacher.
1.Thank you. I am happy to be here.
クラスに参加できてうれしいということを丁寧に伝える表現です。
2.Thank you. How are you?
ありがとう、先生に挨拶する流れです。
A) Thank you!-a polite expression used when acknowledging a gift, service, or compliment, or accepting or refusing an offer.
Example-"thank you for your letter"
B) Thank you . I am excited to be here
*Excited-very enthusiastic and eager.
Example-"they were excited about the prospect"
*Here-in, at, or to this place or position.
Example-"they have lived here most of their lives"
I hope this helps :-)
A) Thank you!
これは貰いもの、誉め言葉、申し出を了承したり拒否された際などに、丁寧にお返事する表現です。
例：thank you for your letter"
（お手紙ありがとう！）
B) Thank you . I am excited to be here
*Excited-すごく情熱的で、熱心な
例-"they were excited about the prospect"
（彼らはその可能性にわくわくしていた。）
*Here-ここで、この中に、ここへ、など
例-"they have lived here most of their lives"
（彼らは人生のほとんどをここで住んでいる。）
I hope this helps :-)
You can say :
Thank you.
I am happy to have the lesson with you.
I am excited.
I am pleased to be here.
Great to meet you.
言い方はいろいろあります。
Thank you.
ありがとう。
I am happy to have the lesson with you.
一緒にレッスンできてうれしいよ。
I'm excited.
わくわくしてるよ。
I am pleased to be here.
ここにいて嬉しいよ。
Great to meet you.
お会いできてうれしいです。.
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