Đề ôn thi Đề thi vào lớp 10 Trường Phổ thông Năng khiếu môn Tiếng Anh - Mã đề PTNK-24

An alloy is a material that is made by combining a metal with at least one other element. While the principal component is usually a metal, the other elements can be either metals or non-metals. The purpose of creating an alloy is to produce a new substance which has improved characteristics compared to its individual components. Essentially, an alloy is a special mixture designed for better performance.

Pure metals often have limitations. For example, pure iron rusts easily and pure aluminum is quite soft. By mixing them with other elements, we can create alloys with more desirable properties. Stainless steel, for instance, is an alloy of iron and chromium and is known (21) __________ its powerful resistance to rust. Similarly, adding copper to aluminum creates duralumin, a much stronger and harder material which is used in aircraft construction.

The process of creating an alloy is technically demanding. First, the component metals are melted at very high temperatures in a large furnace. This is a process that requires extreme heat and careful control. Once the metals are in a liquid state, they are mixed together in very precise proportions. The specific amount of each component is critical because it determines the final properties of the alloy. Finally, the liquid mixture is allowed to cool and solidify, forming the new material.

There are thousands of different alloys used in our daily lives. Bronze, an alloy of copper and tin, was one of the first alloys ever created by humans and was used for tools and weapons. (22) __________, steel is arguably the most important alloy today, essential for building everything from skyscrapers to cars. (23) __________ different types of steel exist, each designed for a specific purpose, such as surgical steel for medical instruments or high-carbon steel for durable tools.

In conclusion, alloys are a fundamental part of modern materials science. By carefully blending different elements, we can engineer materials that are stronger, lighter, or more resistant to corrosion than their original forms. As technology advances, new alloys are constantly being developed, and they continue to (24) __________ a crucial role in industrial progress.

Ho Chi Minh City's eagerly anticipated metro launch signifies more than just faster commutes; it heralds a significant shift in urban culture. Globally, new mass transit systems require citizens to adapt to different social norms for sharing public spaces. The HCMC Metro Line 1 isn't merely infrastructure; it's a new social arena, challenging us to reconsider how we behave in shared environments. The critical question isn't only "Will it speed up our travel?" but "Will it reshape our collective public conduct?" This is an invitation for civic evolution.

This cultural adaptation involves mastering new etiquette. [I] Will people instinctively form orderly queues, allowing clear exits before boarding? Will younger passengers readily offer seats to the elderly, pregnant, or disabled? [II] These aren't trivial suggestions; they are unwritten social contracts ensuring a smooth, respectful experience. [III] Adopting these habits is essential for efficient, pleasant metro operation, transforming chaotic crowds into orderly communities.

[IV] The rationale behind these behavioral expectations centers on collective well-being. Orderly queuing prevents chaos and speeds up boarding. Offering seats is a simple, powerful act of empathy, fostering community over individual comfort. Maintaining cleanliness demonstrates respect for fellow passengers and public investment. When everyone adheres to these norms, journeys become less stressful, more predictable, and genuinely positive. It elevates a functional commute into a shared, civil space, reflecting the city's maturity and citizens' consideration.

For young people, particularly 14-15 year olds, this metro will become an integral part of daily life. Imagine using it for school, meeting friends, or exploring new city areas. This new transport mode will be a constant backdrop to their teenage years. Understanding and adopting the metro's unwritten social rules will be crucial. It's not just about routes; it’s about actively contributing to a polite and efficient environment. Your actions directly influence the experience for everyone, including your peers, shaping the new norm.

Ultimately, the HCMC Metro Line 1's success hinges on users embracing a new public culture. It offers an unparalleled chance for the city to cultivate greater civic responsibility and mutual respect. By consciously adopting habits like queuing, seat-giving, and cleanliness, each individual contributes to a harmonious and efficient public space. This transcends merely riding a train; it's about collaboratively building a more considerate urban society, one journey at a time, where public spaces reflect the finest qualities of its people.