on thorns

continuously uneasy, especially in fear of being detected

焦慮不安，如坐針氈（尤指擔心被察覺）

there is no rose without a thorn

(proverb)every apparently desirable situation has its share of trouble or difficulty

(諺)沒有無刺的玫瑰；世上沒有十全十美的事；有樂必有苦

a thorn in someone's side (或 flesh)

a source of continual annoyance or trouble

經常使人苦惱（或生氣）的事（或人）

the pastor has long been a thorn in the side of the regime.

這個牧師長期以來一直是令這個政權頭疼的人物。