名詞 thorn:

1. something that causes irritation and annoyance
   同義詞：irritant
2. a small sharp-pointed tip resembling a spike on a stem or leaf
   同義詞：spine, prickle, pricker, sticker, spikelet
3. a Germanic character of runic origin

1. He stepped on a sharp thorn.
   他踩到一根尖刺。
2. His sister is a thorn in his flesh.
   他的妹妹使他傷透腦筋。