Proto-Sino-Tibetan: *Krŏ ( ~ -ǝ̆w)
Meaning: toil, endeavour
Tibetan: ãgru-ba to bestow pains upon a thing, ãgrus-pa zeal, diligence, endeavour.
Burmese: ? Burm. khǝw to be lazy; to spare; khrǝwh-khram to be ascetical, sparing; khjǝwʔ to be incomplete, insufficient, deficient
Comments: Perhaps 2 roots.