I chance upon this this article on Yahoo yesterday morning.
Once I started reading it, it reminds me of DB. English is his native language. Yes, his spoken English is, of course, better than mine plus all the slang and some phrases that really get me “urh….”, however, I have to say his spelling sucks to high heaven. English is my second language or is it third? 
After going through ESL (English as Second Language) classes and writing classes at the community college, my writing improved, way better when I first got here, although my spoken still sucks.
Anyway, I want to say is this. DB’s usage of “you’re” and “your” is so apparent, it just irks me to death. Example, “Your welcome.” Drives me nuts seeing that on text or emails.
And when he writes “The dogs are board.” I have to read that sentence again to get the meaning. It should be “bored” not “board”. Another one I see very often amongst my coworker is “tasty”. Some of them write “taste” and DB spell it that way too when I say the chicken was tasty. Another big one this manager uses is “my bad”. I think that is slang but it’s not a proper sentence and I’m picking up on it once in a while and I will catch myself once I say it and then correct myself. I will say, “It’s my fault/mistake.”
Oh since I’m at it, he still says for example, “I doesn’t like the shirt.” WTH, right? I have to correct him, “I don’t like the shirt.” Sometimes I know he is saying it wrong on purpose but in emails and when I read his cover letters, I have to correct his grammar and spelling and like the article said, spell check do not check some words that are not right for the sentence.
Not boasting here but I told him he should be teaching me English, not the other way around. Yes, no?