改开

改开	gǎi kāi	reform and opening up (Chinese policy introduced in 1978) (abbr. for 改革开放)
改	gǎi	to change / to alter / to transform / to correct
开	kāi	to open (transitive or intransitive) / (of ships, vehicles, troops etc) to start / to turn on; to put in operation; to operate; to run / to boil / to write out (a prescription, check, invoice etc) / (directional complement) away; off / carat (gold) / abbr. for Kelvin, 开尔文 / abbr. for 开本, book format