Đề ôn thi Đề thi vào lớp 10 Trường Phổ thông Năng khiếu môn Tiếng Anh - Mã đề PTNK-80

In our solar system, among the many moons orbiting the giant planets, Europa stands out. It is one of Jupiter’s largest moons, but its appearance is quite different from others. While many celestial bodies are covered in craters, Europa’s surface is remarkably smooth. However, it is also covered in long, dark cracks, giving it a very unusual appearance. This mysterious look is one reason why scientists are so interested in it.

The main reason for this scientific interest is the strong possibility that a vast ocean of liquid water exists (21) __________ its icy shell. Scientists believe this ice shell could be several kilometers thick, but under it, there might be an ocean of salty water. This ocean could contain more water than all of Earth's oceans combined. The presence of liquid water, which is a key ingredient for life as we know it, makes Europa an extremely compelling target for exploration.

What is the evidence for this hidden ocean? The cracked surface suggests that the ice shell moves and shifts, which could be caused by an ocean below. Additionally, data from the Galileo spacecraft showed that Europa has a weak magnetic field that changes as it orbits Jupiter. The gravitational pull of Jupiter has a significant (22) __________ on Europa's interior, possibly creating enough heat to keep the water liquid. This is considered strong evidence for a subsurface ocean.

The implications of finding liquid water are enormous. (23) __________, the discovery of an ocean would make Europa one of the most likely places in our solar system to find extraterrestrial life. Although this life might only be microscopic organisms, the discovery would be revolutionary. This is why future missions are being planned to explore this possibility in more detail, with some planning to land a probe on the surface.

In conclusion, Europa is not just another moon. It is a world of incredible potential. Its smooth, cracked surface and the tantalizing possibility of a hidden ocean make it one of the most exciting objects for planetary scientists to study. (24) __________ new piece of information from missions like the upcoming Europa Clipper brings us closer to understanding this mysterious world and answering the question: are we alone in the universe?

Is the ground beneath our feet in danger? This crucial question, often overlooked, increasingly demands an affirmative answer. Soil, a fundamental resource vital for all life, faces a severe threat: degradation. This decline in soil quality, primarily from improper human activities, is a serious environmental problem silently undermining global food security and ecosystem health. Understanding this invisible issue is paramount, as its consequences extend far beyond fields, affecting everyone and our planet's future. [I]

Soil degradation involves the deterioration of soil’s physical, chemical, and biological properties. Imagine soil as a living system, rich with nutrients and organisms crucial for plant growth. When disturbed, it loses fertility and structure. Key causes include intensive farming depleting nutrients, excessive chemical fertilizers/pesticides, deforestation leading to erosion, and poor irrigation causing salinization. These practices exhaust soil, making it less productive and vulnerable to desertification, directly threatening global food availability. [II]

This global challenge resonates deeply in Vietnam, where agriculture is central to the economy and culture. [III] For decades, farmers heavily relied on chemical fertilizers to boost yields. While initially productive, prolonged overuse significantly degraded the soil, diminishing its natural fertility. Recognizing this, the Ministry of Agriculture and Rural Development, with local communities, promotes sustainable farming to restore soil health and secure Vietnamese agriculture's future.

Why should a 14 or 15-year-old care about the dirt under their shoes? The connection is direct: healthy soil is essential for growing the food on your dinner table daily. From rice to vegetables, almost everything you consume originates from healthy soil. If our soil degrades, farmers will struggle to produce enough, potentially leading to higher prices or shortages. This invisible resource directly impacts Vietnam's farming future, affecting your daily meals and the nation's long-term economic well-being. [IV]

Ultimately, our planet's and our own well-being are intrinsically linked to soil health. Soil degradation is complex, but solvable through awareness and collective effort. By understanding its causes, we can support sustainable practices and advocate for policies protecting this vital resource. The ground beneath our feet may seem silent, but its health powerfully speaks about our collective future. Ensuring its vitality is not just an environmental imperative; it's an investment in a secure and prosperous future for Vietnam and the world.