undergrowth

(US underbrush)n [U] mass of shrubs, bushes, etc growing closely on the ground, esp under trees 灌木丛（尤指大树下的）: clear a path through the undergrowth 从灌木丛中开辟一条小路.

underclothes, undercoat, undercover, undercurrent, undercut, underdeveloped, underdog, underdone, underestimate, underexpose, underexposure, underfed, underfelt, underfloor, underfoot, undergarment, undergird, undergo, undergraduate, underground, underhand, underhanded, underlay, underlie, underline, underling, underlying, undermanned, undermentioned, undermine, undermined, underneath, undernourished, undernourishment, underpants, underpass, underpay, underpin, underplay, underprivileged,