Đề ôn thi Đề thi vào lớp 10 Trường THPT Chuyên KHXH môn Tiếng Anh - Mã đề KHXH-138

The Great Wall of China is one of the world's most (35) __________ structures, stretching for thousands of kilometers. It was not built as a single project but as a series of walls and fortifications by different Chinese dynasties. The primary goal was to create a massive, defensive barrier to protect Chinese states and empires from nomadic groups of the northern steppes. It stands as a powerful symbol of China's historical strength and persistence.

The construction (36) __________ under various emperors and dynasties over a long period. Builders used local materials that were available in different regions. In the mountains, they used stone; on the plains, they used earth and brick. The materials, (37) __________ were selected for their durability and availability, were often carried for long distances by human labor and simple machines.

Many strategic features were built (38) __________ the wall's length. These included watchtowers, troop barracks, and fortresses. (39) __________ watchtower was positioned on a high point to give soldiers a clear view of the surrounding area. From these towers, soldiers could send signals using smoke or fire to warn of an approaching enemy. These parts helped soldiers (40) __________ watch for enemies.

The popular image of the Great Wall as a single, continuous structure is not entirely accurate. (41) __________, it is a complex system of walls, some parallel to each other, with fortresses and other defensive buildings integrated into it. The path of the wall travels across deserts, grasslands, mountains, and plateaus, making it an incredible feat of engineering that adapted to the natural landscape.

Today, the Great Wall is a UNESCO World Heritage (42) __________ and one of the most recognized landmarks globally. It attracts millions of visitors each year who come to walk on its ancient stones and marvel at its scale. The wall is more than just brick and stone; it is a monument to the history and culture of the Chinese people.

On any bus in Ho Chi Minh City or walking down a busy street in Hanoi, it is a common sight: teenagers with headphones on, lost in their own world of music or podcasts. For many young people, personal audio devices are essential for daily commutes, studying, or relaxing. However, this everyday habit may carry a hidden risk. The World Health Organization (WHO) has issued a serious warning, stating that over a billion young people worldwide are at risk of permanent, avoidable hearing loss due to unsafe listening practices.

But how does this damage happen? Inside our ears are extremely delicate hair cells that vibrate in response to sound waves and send signals to our brain. When exposed to loud noises for extended periods, these hair cells can be damaged. Unlike other cells in our body, once these are destroyed, they do not grow back. The damage is often gradual and irreversible. The loudness of sound is measured in decibels (dB). While a normal conversation is around 60 dB, prolonged exposure to any sound over 85 dB—the level of heavy city traffic—can begin to cause permanent harm.

So, how loud is too loud? Many smartphones and music players can reach volumes as high as 100-115 dB, which is dangerously loud and can cause damage in less than 15 minutes of listening. A major problem, especially in urban environments like Vietnam's major cities, is ambient noise. To block out the sound of traffic and crowds, listeners often increase the volume to unsafe levels. This practice significantly increases the risk of Noise-Induced Hearing Loss (NIHL).

The initial signs of hearing damage can be subtle. Young people might experience tinnitus, a constant ringing or buzzing in their ears, or find it difficult to hear conversations clearly in noisy environments. A dangerous cycle can begin: as their hearing slightly worsens, they might turn up the volume even more to compensate, which in turn causes further damage. Many teens are unaware that the choices they make about their volume levels today could have a lasting impact on their quality of life for decades to come.

Fortunately, preventing hearing loss is straightforward. Experts recommend the “60/60 rule”: listen at no more than 60% of your device’s maximum volume for no more than 60 minutes at a time before taking a break. Investing in noise-cancelling headphones can also be a wise choice. They work by reducing external sounds, allowing you to enjoy your audio at a lower, safer volume. Ultimately, protecting your hearing is about being mindful. By making small, conscious changes now, you can ensure you continue to enjoy the sounds you love for a lifetime.