Sober English teacher circles something hard to miss (6)
I believe the answer is:
sitter
'something hard to miss' is the definition.
(a sitter is an easy shot)
'sober english teacher circles' is the wordplay.
'sober' becomes 'tt' (I've seen this in other clues).
'english' becomes 'E' (abbreviation).
'teacher' becomes 'sir' (way of addressing a male teacher).
'circles' is an insertion indicator.
'tt'+'e'='tte'
'tte' put inside 'sir' is 'SITTER'.
(Other definitions for sitter that I've seen before include "Artist's model or child's minder" , "One minds the baby" , "Baby minder for pay" , "one can't stand?" , "Extremely easy task" .)