undertake

vt.着手做，从事，承担；保证，答应

undersea, underseal, undersell, undershirt, undershorts, underside, undersigned, undersized, underslung, undersold, understaffed, understand, understandable, understandably, understanding, understate, understated, understatement, understood, understudy, undertaker, undertaking, undertone, undertow, underutilize, undervalue, underwater, underwear, underweight, underwent, underworld, underwrite, underwriter, undeserved, undeservedly, undeserving, undesignated, undesirable, undesirably, undetectable,