in ancient Chian,people used to b____ water over the fire in the open air

in ancient Chian,people used to b____ water over the fire in the open air
in ancient Chian,people used to b____ water over the fire in the open air

in ancient Chian,people used to b____ water over the fire in the open air
boil煮沸,煮（水）
整句翻译为：在古代中国,人们常常在露天的环境下,把水放在火上煮沸.