Email is taking a lot of flak lately. And why not? We're inundated with it. It's cold and impersonal. People abuse it passive-aggressively for their own political agendas. And it can be --to be frank -- addictive.

Yet, no matter how much we gripe about it, and whatever options may be out there like Slack, email is here to stay. For now, at least.

But we can all do email better. Much better. I've been witness to --and often the victim of --a range of email offenses in my working life. And yet, even today, I see people continue to commit the same email offenses that I thought would have become forgotten or even outlawed by now.

So in the interest of raising awareness around these offenses, and with the hope that we can see them committed far less frequently, here are five difficult and uncomfortable things that you should never, ever put into your emails at work. Especially if you want to build --and keep -- the relationships that matter to you most.

1. Delivering formal performance feedback for the first time.

This is a tricky one. It is often necessary to email a performance evaluation before a live conversation. But it should come either immediately before the conversation, or delivered just as the conversation is getting started. Managers who hide behind email to deliver the tough performance feedback they should be delivering in-person (or at least by phone or videoconference) look weak.

2. Criticizing someone while copying others.

I don't know what it is about email that lulls people into thinking it's a better, more humane way to deliver harsh feedback to others. It's not. Criticizing someone point blank in an email, with one or more people in the "cc" field, is really no different than berating someone at a meeting with other colleagues present. It's humiliating to the person on the receiving end of the tirade, and it makes the perpetrator look like a bully.

3. Criticizing someone while blind copying others.

Okay, since putting others in the visible "cc" field of your critical email shames the person, then why not hide the names of those you copy by slipping them into the blind copy, or "bcc" field. That will shield the person from embarrassment and make you look more humane, right?

Wrong. This is not only duplicitous, it's downright dangerous. Ever have someone who was blind copied in an email hit "reply all", exposing the fact you had secretly shared your note to them? I have. And it's not fun.

4. Including long email histories in your replies.

This is especially irksome for a couple of reasons. First, long histories become irrelevant and invite unneeded and wasteful reading of them. Second, they expose you to conversations that are better kept confidential. I've seen this both in emails that were circulated internally and in incoming emails from external sources. Sometimes, emails included private conversations that were not meant for my eyes or anyone else's.

5. Informing someone of really bad news.

Years ago, a colleague sent me a brief email informing me that someone close to me had died. Needless to say, I was shocked and devastated by the news. Why couldn't she have called me and provided more context and offered a sympathetic ear? Please, don't inflict this pain on others. If you are the bearer of extremely unfortunate news, then deliver it in person, or at least by phone.