"I can’t find the mail about our next project. Can you forward the mail to me?"
"I got a useful email on productivity. I think I will forward it to our team."
"I have that email. I’ll forward it to you."
"If you find that mail, please forward it to me."
"I’ll forward you the mail I got from the manager."
"I received a mail from the marketing manager. I don’t know what she is asking for. Can I forward the mail to you?"
"One of our clients is asking for more data on the BB project. Who should I forward this mail to?"
"Forward the complaint to the manager. I think he should see this."
Sending to an alternate email address is common when the work email is not working. Here are some sentences you can use if you are ever in this situation. Some companies do not allow this, so make sure your company does not have policies prohibiting this.
"My work email is currently down. Can you send it to my personal email address? It is email@example.com."
"I’m having problems with my work email account. Can you send it to firstname.lastname@example.org instead?"
"I’m having problems sending you an email to this account. Is there another email account you have that I can try?"
"Our exchange server is down for the next thirty minutes. If this is urgent, you can send me an email to my personal account. It is email@example.com."
Although I a couple of sentences on writing email sentences, most of this is to talk about email. Learning to write is not what I am trying to teach here. I want everyone to be able to speak. You should be practicing all of these lessons while talking along.