チャットなので動詞に"message"を使うとよりそれっぽくなると思いますよ。
あと一つの文章に「素早く」「たくさん」と詰め込まず、まずは「素早く書いてくれてありがとう」と言った方がベターです。そのあとに「たくさんのメッセージうれしい！」みたいな文章を入れましょう。
"Thank you for quickly messaging through Chat."
"I'm happy to have your a lot of massages!"
Thank you for further assisting me by writing the answer in the chat box.
These are very good ways of saying thank you to your teacher for helping you. You can also simply say thank you. If you would like to be short and sweet!
Thanks for typing the answers so quickly, teacher!
It's really useful to me when you type the answer so quickly, teacher!
You may either thank the teacher directly:
"Thanks for typing the answers so quickly, teacher!" or, you may express how useful the quick writing of the answers is for you:
"It's really useful to me when you type the answer so quickly, teacher!"
"It's my pleasure! I attended secretarial school a few years ago and learned to touch-type there."
To touch type = to use all your fingers on the keys when typing. Touch typing typically involves placing the eight fingers in a horizontal row along the middle of the keyboard (the home row) and having them reach for other keys.
率直にお礼を言う事も出来ます。
"Thanks for typing the answers so quickly, teacher!"
（答えを素早く入力してくれてありがとうございます）
又は、素早い入力がどんなに役に立っているか言い表すことも出来ます。
"It's really useful to me when you type the answer so quickly, teacher!"
（先生が素早く答えを入力してくれるので大変役に立っています）
"It's my pleasure! I attended secretarial school a few years ago and learned to touch-type there."
（どういたしまして！数年前に秘書に必要な技術を身に着けつ学校でタッチタイピングを学んだんですよ）
To touch type = キーを見ないで打つ
Touch typing(タッチタイピング)では8本の指を真ん中のキー(the home row)沿いに横一列に並べて、他のキーも入力するようにします。
If you want to tell someone you appreciate something then you can say 'thanks' or 'thank you'
by doing something quickly means you do it just after it has happened
Thank you for writing the correct answer so quickly!
Thank you for helping me
Thank you for assisting with the chat box so quickly!
three very easy, Polite, often used and convenient ways of thanking your teacher for helping quickly and efficiently.
'Assisting' is also another word to describe helping someone.
Another way to thank someone is to tell them that you appreciate them or something that they do. Sometimes, this can be seen as more genuine than just saying thank you. I hope that this helps! :)
I appreciate _____'（_____に感謝します）でも、感謝の気持ちを伝えることができます。これは時に "thank you" よりも心がこもっていると見られることがあります。
参考になれば幸いです！
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