Butterflies belong to insects. They have no backbones in their bodies and belong to invertebrates. Its body is divided into three parts: head, chest and abdomen. The head has a pair of tentacles, a pair of compound eyes and a pair of monocular eyes, in which the tentacles have the functions of touch and smell. This insect has an exoskeleton on its body surface, which can protect, support and prevent the evaporation of water in the body. It has three pairs of feet and two pairs of wings, and it is very athletic.

Test center: This question examines the main characteristics of insects.

Comments: This topic is called basic knowledge. The key to solve this problem is to remember the characteristics of insects.