Communication
Being able to communicate effectively is the most important of all life skills.
Communication is the act of transferring information from one place to another, whether this be vocally , written , visually or non-verbally (using body language, gestures and the tone and pitch of voice).
With the advancement of technology and the now more common use of emails, texts, communication apps etc., it is even more important to consider how you write your message to convey the correct tone and intent of that message. Put yourself in your recipients position and read your message as if it were being sent to you. This will help in getting your message across more effectively and hopefully in the intended tone. It is very easy to send a message with one intent and it being received in a totally different intent.
In today's competitive world, the last thing you want is to send a message that may be misunderstood and potentially lose you a lead or a client.
I never turn away a request for advice or counsel, especially from a student or new graduate. I am humbled by the opportunity. I tell them all the same thing every time. Get command of the English language and become adept at presenting yourself (meaning your case, your proposal, your solution, your plan, your desire, etc.) to a group, be that group one or one dozen or one thousand and the clutter that is the world will part before you, opening a clear path to wherever you want to go. To your specific point, Danny, way back when I was early to the quest to improve my own skills, I learned (source unknown) Rule 1. of communication: Consider the audience. Rule 2. is: Ensure Rule 1. is satisfied before proceeding!