第15单元

Parachuting is a sport where a person jumps from an aircraft and uses a parachute to slow their descent and safely land on the ground. The jump is typically made from high altitudes, and the parachute is deployed either manually or automatically after a certain height. Parachuting can be done solo or with an instructor. It is a thrilling activity that requires training, proper equipment, and safety measures. The sport allows participants to experience freefall and enjoy the view during their descent before the parachute opens.

A pigeon is a versatile bird, known for its plump body, short neck, and distinctive cooing calls. Found worldwide, pigeons come in a variety of species and exhibit a range of colors and patterns. They have adapted well to various environments, including urban areas, where they form flocks and become a common sight. Pigeons display remarkable homing abilities and have been used for centuries as messengers. With their herbivorous diet consisting of seeds, grains, and fruits, pigeons play an important ecological role as seed dispersers. Their gentle cooing calls add a soothing ambiance to parks and city streets, while their adaptability and resilience make them a fascinating and ever-present part of our urban landscapes.

A leash is a long, flexible, and typically slender material, such as a strap or cord, used to restrain or guide an animal. It is commonly attached to a collar or harness worn by the animal, allowing its movement to be controlled by the person holding the other end of the leash. Leashes come in various lengths and materials, such as nylon or leather, and often feature a handle for easy gripping. They serve as a means of ensuring the safety and control of the animal during walks, training sessions, or other activities. Leashes provide a physical connection between the animal and its owner, allowing for better management and communication between them.

A helmet is a protective headgear designed to protect the wearer's head from injuries caused by impacts, collisions, or falling debris. It is typically made from hard, durable materials such as metal, plastic, or Kevlar, and features a cushioned lining that provides shock absorption and comfort. Helmets are widely used by military personnel, law enforcement officers, construction workers, athletes, and individuals engaging in extreme sports such as cycling, skiing, and rock climbing. Some helmets also come equipped with additional features such as ventilation, visors, and communication systems. Properly fitting and correctly worn helmets can significantly reduce the risk of head injuries in accidents.

An article is a written work that focuses on a specific topic, typically published in newspapers, magazines, journals, or online platforms. Articles are designed to inform, explain, or discuss particular subjects in detail, and they can vary in length, style, and complexity. They may present facts, opinions, research findings, or analysis, depending on the purpose and audience. Articles are commonly written by journalists, experts, or researchers, and they are often structured with a headline, introduction, body, and conclusion to convey information clearly and effectively.

Healthcare refers to the services and practices aimed at maintaining or improving people's health. It includes a wide range of activities, such as medical treatments, preventive care, diagnosis, and health education. Healthcare can be provided by doctors, nurses, therapists, and other medical professionals in various settings, including hospitals and clinics. The goal of healthcare is to ensure individuals receive the care they need to stay healthy, manage illnesses, and recover from health issues.