回信的单词怎么写

1.to write in reply; to write back; to answer a letter; to reply to one's letter
2.a letter in reply; an acknowledgement
3.a verbal message in reply

write back 是回信的意思。

I'll write you back.

如果是email的话

email back.

reply to 答复

v reply
谢谢您及时地回信
Thank you for replying immediately.

reply
waiting for your early reply.

reply.