多少

多少 (duōshao) is the standard question word for asking 'how many' or 'how much' when the answer could be any number — large or small, countable or uncountable. Literally 'many-few,' it differs from 几 (jǐ) in one important way: 几 expects a small answer (under ten, usually) and almost always takes a measure word (几个人 'how many people'), while 多少 expects any number and the measure word is optional (多少人 or 多少个人). Use 多少 for prices (多少钱 'how much money'), phone numbers, ages of adults, large quantities, and anything where you have no estimate. Note: the second syllable is the neutral tone shao, NOT shǎo — duōshao together is the question word; duō shǎo as two stressed syllables means 'more or less'.

Memory hook: 'Many-few?' — literally asking 'how far on the many-to-few scale?' i.e. how much.