"flap"@en-us . "move in a wavy pattern or with a rising and falling motion; \"The curtains undulated\"; \"the waves rolled towards the beach\""@en-us . . . "wave"@en-us . "201901783"^^ . . . . . . . "undulate"@en-us . . . . . . "0"^^ . "01901783-v"^^ . . . . . . "roll"@en-us . . "0"^^ . "201846240"@en-us . "roll"^^ . .