名詞
形容人夠眼利，能夠識別真偽；本來指《西遊記》主角孫悟空嗰對睇得穿妖怪變化術嘅眼睛 (of people) keen eyes able to discern the real from the fake; literally: gold pupils and fiery eyes (the Monkey King's eyes which can recognize the monsters through their human make up in "Journey to the West")
呢批畫有真有假，要靠你對金睛火眼幫我分辨下嘞。
呢批画有真有假，要靠你对金睛火眼帮我分辨下嘞。
ni1 pai1 waa2 jau5 zan1 jau5 gaa2, jiu3 kaau3 nei5 deoi3 gam1 zing1 fo2 ngaan5 bong1 ngo5 fan1 bin6 haa5 laak3. This batch of paintings contains both real and fake ones. I need your keen eyes to tell them apart.
名詞
引申為打醒精神，或長時間不眠不休去進行一件任務。 to be on guard; to remain vigilant; to burn the midnight oil so as to accomplish a task
呢單嘢你一定要金睛火眼幫我睇住。
呢单嘢你一定要金睛火眼帮我睇住。
nei1 daan1 je5 nei5 jat1 ding6 jiu3 gam1 zing1 fo2 ngaan5 bong1 ngo5 tai2 zyu6 For this job I need you to keep a watchful eye.
名詞
引申為長時間工作後眼睛極之疲倦，眼乾又熱似火熱 red eyes resulting from the fatigue of intense concentration; the dry, inflamed eyes are thought to resemble fire
呢單嘢真係捱到我金睛火眼。
呢单嘢真系挨到我金睛火眼。
nei1 daan1 je5 zan1 hai6 ngaai4 dou3 ngo5 gam1 zing1 fo2 ngaan5 This job has left my eyes red and exhausted.