members posts not normal, please help me work it out!!

Hi there! one of my members posts are showing with larger than normal text and a space below his text (represented below with the red arrow). he said that he isnt doing anything and keeps asking me for help to put it right.



i have looked at the text that he is posting and it appears that there is some sort of table code embedded in his posts. he says he isnt doing it. how can i disable what he is doing?? as im not quite sure how to put it right again. (im sure it is something stupidly simple). below is a picture of the code.



thanks in advance!

klik to a/A booton

yes, then what?