If Google Groups isn't available in your work or school account, ask your administrator to turn on Groups for Business. 
Group owners and managers can add a prefix that appears in the subject line of all group messages. This helps recipients quickly identify that the message is from the group.
Add a prefix
- Sign in to Google Groups.
- Click the name of a group.
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On the left, go to Group settings
Email options.
- In the Subject prefix field, enter the text that you want to add to the beginning of email subjects.
Recommended: Use square brackets around the prefix—for example: [Group prefix]. - Click Save changes.
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