回事

(old) to report to one's master

to circle / to go back / to turn around / to answer / to return / to revolve / Hui ethnic group (Chinese Muslims) / time / classifier for acts of a play / section or chapter (of a classic book)

to curve / to return / to revolve

variant of 迴|回[hui2]

matter / thing / item / work / affair / CL:件[jian4],樁|桩[zhuang1],回[hui2]

two quite different things / two unrelated matters

not regard as a matter (of any importance)

not bad at all / quite impressive

what's the matter? / what's going on? / how could that be? / how did that come about? / what's it all about?

to take seriously (often with negative expression: "don't take it too seriously") / to treat conscientiously

erhua variant of 當回事|当回事[dang4 hui2 shi4]

Saying is one thing, doing quite another (idiom)

see 說是一回事，做又是另外一回事|说是一回事，做又是另外一回事[shuo1 shi4 yi1 hui2 shi4 , zuo4 you4 shi4 ling4 wai4 yi1 hui2 shi4]

one and the same (thing) / one thing (as distinct from another)