This may be off topic but I was wondering something. Y'all know that if a mole(on your body) changes in shape or color, you should go to the doctor to have it checked out. I assumed this is common knowledge so I said to someone, "
They say if a mole changes....(etc)...checked out." That person asked me, who are they? I was stumped.

So, who
are they or how should I have phrased the sentence, or am I simply saying it wrong?