I'm totally learning the importance of word choice. I have a tendency to talk quickly without paying attention to the words I'm using, and its gotten me into trouble a few times. For example, last week I did a presentation on my thesis research & I said the word "Should" instead of "Could" (thus making it look like I was TELLING people what to do, not RECOMMENDING) and I swear one of my professors launched an attack on me like it was WWIII as she thought I was telling her how to do her job.
Another example is that I was describing the field I'm in to a friend & I meant to say one of the things we study is literature for the LGBT community ... but I said "we study gay literature" which my friend informed me was offensive. I had no idea .. and then I remembered I had said the exact same thing in an email to one of my POIs. Maybe thats why I was rejected from that school .
But seriously, word choice is very, very important. Especially during things like interviews, presentations, and emails, where what you say during that short period of time represents who you are to that person. I had an interview two days ago & I made sure to talk more slowly, to think about his questions, to pay attention to his reaction to what I said to see if further explanation was necessary (I tend to be very long-winded, which is another problem because the more I talk the more I insert my foot into my mouth) and to be aware of what I was saying at all times.
I also re-read my emails once or twice before sending them to make sure they aren't making sweeping generalizations or saying things that could be taken as offensive. It takes a little work, but it's worth it in the end.