Which of the following is acceptable?
Mi español ha empeorado (mucho).
Mi español se ha empeorado (mucho).
Mi español ha malogrado (mucho).
Mi español se ha malogrado (mucho).
I have been saying 4 a lot but have woken up to the fact that it doesn't mean what I thought it meant, i.e., it suggests my Spanish hasn't attained its natural state of development. Or perhaps not that either - correct me if I'm wrong. I haven't used Spanish in over 15 years. (On the upside, using it the way I have demonstrates perfectly how bad my Spanish has become!)
Which of the above sentences would you recommend using? (No. 2 seems right to me, but then so did No. 4!) Are there any other ways you would express this idea?