The following content is only for discussing the general principles of self-defense concepts and environmental responses. It is by no means an encouragement to use violence or participate in fights, nor can it replace professional combat training. In any situation that may involve personal injury and legal risks, the safest and most sensible approach is always to try to avoid conflict as much as possible and seek police or other professional help as soon as necessary. If you really encounter danger, the following principles may help increase your chances of survival, but please remember: actual combat situations are complex and changeable, and text descriptions cannot cover all the details. It is crucial to participate in formal self-defense training and understand local laws and regulations. 1. Stay observant and calm • In an environment where a conflict may occur, always pay attention to the surrounding situation and assess in advance which objects (such as roadside railings, walls, car bodies, benches, large boxes, trash cans, etc.) can serve as immediate cover or obstacles. • Keep a clear mind and quickly determine the opponent's position and possible attack routes, while paying attention to whether there are safe retreat routes behind and to the sides. 2. Quickly identify and use obstacles • Use natural and artificial obstacles: In street environments, walls, vehicles or other solid objects can form a barrier between you and the attacker, helping you block direct attacks. • Find an advantageous position: For example, standing on one side of an obstacle can reduce attacks from multiple directions and create opportunities to change direction or leave the scene. • Create extra distance: Use obstacles as springboards or shields to temporarily change the rhythm of the battle and buy time to leave the battle as soon as possible. 3. Flexibly use obstacles for defense • Block vision and attack angles: Use obstacles to block part of the vision and force the opponent to reveal the intention of attack, so that you can react earlier. • Use as a buffer or block: Before the opponent gets in close contact, use obstacles as contact points to reduce the damage caused by direct attacks. If conditions permit, try to use the force to counterattack, but be very careful to avoid more damage due to unfamiliarity with the situation. • Use obstacles to create transition space: In actual combat, combine obstacles with your own movements, such as using walls to adjust your steps or using narrow areas to limit the opponent's mobility, so as to buy time to leave or control the situation. 4. Pay attention to safe retreat • Always stay alert to the surrounding environment and never let yourself be trapped in a blind spot or a position where you cannot escape. • If you find that the situation is difficult to control, you should look for opportunities to use obstacles to evacuate quickly and call for help, rather than getting too entangled. 5. Professional training and legal awareness • Any confrontation in actual combat is uncontrollable, so participating in formal self-defense and combat training can help you use the environment more rationally; at the same time, it is very important to understand the legal boundaries and countermeasures of self-defense in combination with regional laws. • Remember that self-defense is essentially to protect yourself, and any unnecessary escalation may have irreversible consequences. In summary, using obstacles in the environment for self-defense is a strategy based on "winning with wisdom" rather than brute force alone. The core lies in familiarity with the environment, quick judgment of the situation, and calm choices. Since the real situation is often more complicated than the theory, it is recommended to attach importance to prevention and training under the premise of legality and safety, rather than relying on improvisation on the spot.