汉译英：很长时间没登陆邮箱，刚刚回复很抱歉。

I haven't check my mailbox for long time. I'm very sorry for answering you so late.

一般用来交流的，不管是说话，还是写信，句子要简短易懂，用些常见的单词。省得产生一些不必要的麻烦。毕竟各人的理解方法不一样的。

I haven't logged into my email. I'm sorry that I replied you so late.

I have not loaded this email box. I am so sorry to respond you for a long time.

I haven't logged in to check my emails for a long while. My apologies for replying so late.

Sorry, I just replied because I haven't logged in for a while.