Kenneth G. Wilson (1923–). The Columbia Guide to Standard American English. 1993.
sparing in, sparing of, sparing with
Sparing of and sparing in are the common combinations: He is sparing of praise for his students. They are sparing in the food they provide their guests. Sparing with occurs only rarely and stiffly, as in Americans are said not to be sparing with their praise of their possessions.
