What recommendations/actions would you provide to a coworker if they did not understand an email that was written by their supervisor?

communicate directly to the supervisor to clarify the intend of the email

Explanation:

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My recommendation would be: communicate directly to the supervisor to clarify the intend of the email

Most employees believed that asking clarification to their supervisor would reflect badly on them since it make them look incompetent.

But most supervisors are trained to provide employees with guidance if they do not understand their assignment. And, following the wrong order would be significantly worse compared to not able to understand an email.