開眼

to open one's eyes / to widen one's horizons

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

to open / to start / to turn on / to boil / to write out (a prescription, check, invoice etc) / to operate (a vehicle) / carat (gold) / abbr. for Kelvin, 開爾文|开尔文[Kai1 er3 wen2] / abbr. for 開本|开本[kai1 ben3], book format

broaden, expand one's horizons

brows raised in delight, eyes laughing (idiom); beaming with joy / all smiles