并回信告知英文

Please write back and let me know if /whether you can come.Please give (me) a reply, telling me if /whether you can come.Please write a letter in reply to inform me (of) whether you can come.

简单 请看qing ni hui xin gao zhi shi fou neng lai

in reply a letter

Re. (口语reply,文字Re.)

Reply the letter

翻译成英语，Tom, I'm very happy that you received my letter and wrote back to me.