眼中钉，肉中刺

a thorn in one's side

eye / small hole / crux (of a matter) / CL:隻|只[zhi1],雙|双[shuang1] / classifier for big hollow things (wells, stoves, pots etc)

in one's eyes

China / Chinese / surname Zhong

within / among / in / middle / center / while (doing sth) / during / (dialect) OK / all right

to hit (the mark) / to be hit by / to suffer / to win (a prize, a lottery)

a thorn in one's side

nail / to follow closely / to keep at sb (to do sth) / variant of 盯[ding1]

to join things together by fixing them in place at one or more points / to nail / to pin / to staple / to sew on

meat / flesh / pulp (of a fruit) / (coll.) (of a fruit) squashy / (of a person) flabby / irresolute / Kangxi radical 130

a thorn in one's flesh

(onom.) whoosh

thorn / sting / thrust / to prick / to pierce / to stab / to assassinate / to murder