Mad guy grabs student: not a pretty sight (4)

I believe the answer is:

ugly

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'not a pretty sight' is the definition.
I can't judge whether this defines the answer.

'mad guy grabs student' is the wordplay.
'mad' is an anagram indicator.
'grabs' means one lot of letters goes inside another.
'student' becomes 'l' (learner, as in L-plates for learner drivers).
'guy' is an anagram of 'ugy'.
'ugy' going around 'l' is 'UGLY'.

Can you help me to learn more?

(Other definitions for ugly that I've seen before include "Unsightly, not pretty" , "Deficient in beauty" , "Lacking in beauty" , "Unpleasant to look at" , "Sullen" .)

I've seen this clue in The Sun.

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