vastadj.巨大的；广阔的vast unpopulated plains.广袤、没有人烟的草原。vast stretches of paddy fields成片的稻田VAST VLAN Advanced Switch Test虚拟局域网高级开关测试vastus medialis rehabilitation股内肌功能康复Vastly expansive and everlasting无始无边Vast distances boggle the mind.距离之大，不可思议。vast stretches of construction area成片建设地区vast population and limited farmland人多地少vast territory and abundant resources地广物博