Inclusion criteria:  2-7 years old, normal consciousness, preschool children who need intravenous injection. 7-12 years old, normal consciousness, school-age children who need intravenous injection. Parents of children need to be conscious and able to talk in Chinese.  Exclusion criteria:  2-7 years old preschool children with developmental delay, epilepsy, heart disease, chemotherapy, visual and hearing impaired, obese, and have received more than 2 intravenous injections. 7-12-year-old school-age children with developmental delay, epilepsy, heart disease, chemotherapy, visual and hearing impaired, obese, and have received more than 2 intravenous injections. The child's parents cannot express and communicate effectively.