Student or Learner
Does this make sense? Maybe "dressed in black" is mostly heard, but in rare cases, "dressing" as an intransitive verb can be possible.
17)The woman dressing in black is my boss.
If you're pointing out your boss while she is in the process of getting dressed, you must have a slightly odd job!
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.