You end up becoming this perky, gung-ho version of yourself that you know is just revolting.
-- Douglas Coupland, Microserfs
It's not because he's such a gung-ho company man, he's too smart for that.
-- Jonathan Franzen, Strong motion: a novel
Gung ho introduced as a training slogan in 1942 by U.S. Marine officer Evans F. Carlson (1896-1947) from the Chinese chin gōng hé, the abbreviated name of the Chinese Industrial Cooperative Society, literally "work together."