VOA慢速英语:许多帝王蝶不飞往南方过冬

straggler – n. a person or animal that moves slower than others and becomes separated from them

habitat – n. the area where a plant, animal or insect normally lives

pesticide – n. a product that kills animals or insects that damage crops

milkweed – n. a type of North American plant that has white juice

caterpillar – n. a small creature that is like a worm with many legs and that changes to become a butterfly or moth