Đề ôn thi Đề thi vào lớp 10 Trường Phổ thông Năng khiếu môn Tiếng Anh - Mã đề PTNK-168

The ancient Romans were famous for their engineering skills and grand constructions. Their cities featured magnificent temples, public baths, and arenas that still stand today. One of their most (21) __________ innovations was the semicircular arch, a simple but revolutionary design. This structure fundamentally changed how buildings were designed and constructed across the Roman Empire.

Before the arch, builders used a simple post-and-lintel system, which involved placing a horizontal beam across two vertical posts. This method had significant limitations, especially for creating wide openings. The Roman arch was a (22) __________ solution because it could span much wider distances without needing many columns for support.

The secret to the arch's strength lies in how it distributes pressure. It was built using several wedge-shaped stones, called voussoirs, which were placed in a curved line. When weight was put on the arch, the stones pushed against each other, directing the pressure sideways and then down into the ground. This meant that no single stone carried too much weight. The most (23) __________ piece was the keystone, the final wedge-shaped stone placed at the top of the arch.

The keystone locked all the other stones into position. Without it, the entire structure would collapse under pressure. Not only did this design allow for bigger and stronger buildings, but it also enabled the construction of enormous aqueducts that carried water for many kilometers. These structures helped the Romans (24) __________ a massive and sophisticated empire.

Overall, the Roman arch was more than just an architectural feature. It was a foundational technology that demonstrated a deep understanding of physics and materials. The principles behind the Roman arch, which are based on managing compression and tension, continue to influence engineering and architecture to this very day.

Many of us instinctively reach for snacks marketed as "healthy," believing we're making a smart choice for our well-being. Food companies worldwide expertly position products like granola bars, fruit yogurts, and baked chips as guilt-free alternatives. These items often come in attractive packaging, adorned with images of fresh produce or active lifestyles, subtly implying nutritional benefits. Yet, a surprising truth often hides: many so-called healthy snacks are stealthily loaded with ingredients that undermine their perceived goodness. [I]

[II] Walk into any major supermarket like Co.opmart or GO! (formerly Big C), and you’ll notice an expanding section dedicated to these seemingly nutritious offerings. Both imported and local Vietnamese brands capitalize on growing demand from families eager to make healthier choices. While their presence indicates a positive shift towards awareness, it also highlights the challenge of distinguishing genuinely beneficial foods from clever marketing ploys. [III]

For teenagers aged 14-15, these snacks often seem ideal for a busy lifestyle. Rushing between classes or to sports, a quick grab-and-go item offers immense convenience. You might naturally pick a colorful package labeled "natural" or "low-fat," assuming it’s the best option. However, relying solely on marketing can be misleading. Understanding what truly fuels your growing body is crucial, as informed snack choices directly impact your energy and focus daily. [IV]

The deception often lies in hidden ingredients. Many granola bars, despite their wholesome image, contain high amounts of added sugars, often listed under various names like corn syrup or cane juice. Fruit yogurts, while containing some fruit, can be packed with artificial sweeteners and excessive sugar, transforming a healthy dairy product into a sugary dessert. Even baked chips, presented as healthier, might still be high in sodium, refined carbohydrates, and unhealthy fats, offering little nutritional value.

So, how can you navigate this confusing landscape? Your most powerful tool is the nutrition label. Before buying, read it carefully. Pay attention to added sugar, aiming for minimal amounts. Check saturated and trans fat levels, and look for fiber, which helps you feel full. Instead of processed "healthy" snacks, consider whole, unprocessed alternatives like fresh fruits, unsalted nuts, or plain yogurt. Being label-savvy empowers you to make genuinely healthy choices for your body.