1 Aerobatics（特技飞行） is the practice of flying maneuvers （演习）involving aircraft attitudes that are not used in normal flight. Aerobatics are performed in airplanes and gliders for training, recreation, entertainment, and sport.2 BMX or Bicycle （自行车越野赛）motocross is a cycle sport performed on BMX bikes, either in competitive BMX racing or freestyle BMX, or else in general on- or off-road recreation. BMX began when young cyclists appropriated motocross tracks for fun, racing and stunts, eventually evolving specialized BMX bikes and competitions.3 Cave diving(洞穴潜水) is underwater diving in caves which are at least partially filled with water. Cave diving is generally considered to be a type of technical diving due to the lack of a free surface during large parts of the dive, and often involves decompression.4 Ice climbing（攀登冰坡） is the activity of ascending inclined ice formations. Usually, ice climbing refers to roped and protected climbing of features such as icefalls, frozen waterfalls, and cliffs and rock slabs covered with ice refrozen from flows of water5 Mountaineering(登山) is the sport, hobby or profession of hiking, skiing, and climbing mountains. While mountaineering began as attempts to reach the highest point of unclimbed big mountains. All require experience, athletic ability, and technical knowledge to maintain safety6 Paragliding（高崖跳伞运动） is the recreational and competitive adventure sport of flying paragliders: lightweight, free-flying, foot-launched glider aircraft with no rigid primary structure. The pilot sits in a harness suspended below a fabric wing consisting of a large number of interconnected baffled cells. 7 Parkour (跑酷)is a holistic training discipline using movement that developed from military obstacle course training.Practitioners aim to get from A to B in the most efficient way possible.They do this using only their bodies and their surroundings to propel themselves. Parkour can include obstacle courses, running, climbing, swinging, vaulting, jumping, rolling, quadrupedal movement.8 Rallying（汽车拉力赛） is a form of auto racing that takes place on public or private roads with modified production or specially built road-legal cars. Rallies may be won by pure speed within the stages or alternatively by driving to a predetermined ideal journey time within the stages9 Rock climbing（攀岩） is an activity in which participants climb up, down or across natural rock formations or artificial rock walls. The goal is to reach the summit of a formation or the endpoint of a usually pre-defined route without falling. 10 Skydiving（跳伞运动)is the action sport of exiting an aircraft and returning to Earth with the aid of gravity, then slowing down during the last part of the descent by using a parachute（降落伞). 11 Skimboarding（潜水冲浪） is a boardsport in which a skimboard is used to glide across the water's surface to meet an incoming, breaking wave, and ride it back to shore. 12 Snowboarding（单板滑雪） is a winter sport that involves descending a slope that is covered with snow while standing on a snowboard, a board attached to a rider's feet, using a special boot set into a mounted binding13 Surfing（冲浪） is a surface water sport in which the wave rider rides on the forward or deep face of a moving wave, which is usually carrying the surfer towards the shore. 14 Whitewater kayaking（皮艇运动） is the sport of paddling a kayak on a moving body of water, typically a whitewater river. Whitewater kayaking can range from active, moving water, to demanding, extreme whitewater15 Windsurfing（帆板运动） is a surface water sport that combines elements of surfing and sailing. It consists of a board usually 2 to 3 metres long, with a volume of about 60 to 250 liters, powered by wind on a sail. 16 Wingsuit flying （飞鼠装滑翔运动） is the sport of flying the human body through the air using a special jumpsuit, called a wingsuit, which adds surface area to the human body to enable a significant increase in lift. 17 Wakeboarding （尾波滑水）is a surface water sport which involves riding a wakeboard over the surface of a body of water. It was developed from a combination of water skiing, snowboarding and surfing techniques.18 Bungee jumping（蹦极） is an activity that involves jumping from a tall structure while connected to a large elastic cord. The tall structure is usually a fixed object, such as a building, bridge or crane; but it is also possible to jump from a movable object, such as a hot-air-balloon or helicopter.19 。