兩

two / both / some / a few / tael, unit of weight equal to 50 grams (modern) or 1⁄16 of a catty 斤[jin1] (old)

lit. two segments with a single cut (idiom) / fig. to make a clean break (idiom)

one move, two gains (idiom); two birds with one stone

two or three

one country, two systems (PRC proposal regarding Hong Kong, Macau and Taiwan)

lit. twice every three days (idiom); practically every day / frequently

(of marriage or business partners) to break up (idiom) / to separate

unfamiliar at first but you get used to it / strangers are first meeting, but soon friends / an acquired taste

one person taking on two tasks simultaneously

lit. one body two sides (idiom) / fig. a situation with two sides to it

in twos and threes

quickly and effortlessly (idiom)

lit. to fish for three days and sun-dry the nets for two days (proverb) / fig. not to persevere in doing sth / to do sth by fits and starts

places of pleasure (like brothels, tea houses etc)

repeatedly (idiom)

(idiom) (of marriage or business partners) to break up; to separate

(coll.) to feel as though one's head could explode (Tw)

high quality at bargain price

see 一回生二回熟[yi1 hui2 sheng1 er4 hui2 shu2]

lit. family members speak frankly with one another, not courteously, as if they were from two different families (idiom) / fig. people don't need to be deferential when they ask a family member for help / people from the same family should stick together (and good friends likewise)

to split sth into two (idiom)