Answer:
If you are talking about a guy who is English or who speaks English, you would write it like so:
<em><u>This English guy is on another level.</u></em>
If you were talking about a guy named English, you would write it like so:
<u><em>This guy, English, is on another level.</em></u>
Also, if you were talking about the person's English in general, you would write it like so:
<u><em>This guy's English is on another level.</em></u>
<u><em></em></u>
Hope this helps!