to eat / to consume / to eat at (a cafeteria etc) / to eradicate / to destroy / to absorb / to suffer / to stammer (Taiwan pr. for this sense is [ji2])
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