(Mandarin speakers, avert your eyes while I butcher your (native or LRD acquired) tongue.)
Yes I know us flat-tongued English speakers have a deplorable tendency to apply English phonics to all foreign languages. Thus the ook and seem roles in yay-oi, or the garahdges and chez lounges out in back of the house. And I know half of Mandarin's sounds don't exist in English in the first place, rotit. (Retroflex j's and ch's and sh's, she mutters.) But I gets my mnemonics where I finds them, and when I must deal with oft-recurring modals or tricksy prepositionses, I'll take whatever low means are available to remember them. Thus I present you with Uncle Scrooge's nephews: 会 (hui), 对 (dui) and 里 (li with a dipping tone.) Though you'd think Chinese could come up with a true lui or rui sound...