 Within the range of mass @-@ classifiers , authors have proposed subdivisions based on the manner in which a mass @-@ classifier organizes the noun into countable units . One of these is measurement units ( also called " standard measures " ) , which all languages must have in order to measure items ; this category includes units such as kilometers , liters , or pounds ( see list ) . Like other classifiers , these can also stand without a noun ; thus , for example , <unk> ( bàng , pound ) may appear as both <unk> ( sān bàng <unk> , " three pounds of meat " ) or just <unk> ( sān bàng , " three pounds " , never * <unk> sān ge bàng ) . Units of currency behave similarly : for example , <unk> ( <unk> yuán , " ten yuan " ) , which is short for ( for example ) <unk> ( <unk> yuán <unk> , " ten units of renminbi " ) . Other proposed types of mass @-@ classifiers include " collective " mass @-@ classifiers , such as 一群人 ( yì qún rén , " a crowd of people " ) , which group things less precisely ; and " container " mass @-@ classifiers which group things by containers they come in , as in <unk> ( yì <unk> <unk> , " a bowl of porridge " ) or <unk> ( yì <unk> <unk> , " a bag of sugar " ) . 
