Đề ôn thi Đề thi vào lớp 10 Trường Phổ thông Năng khiếu môn Tiếng Anh - Mã đề PTNK-69

The wheel and axle is one of the six classical simple machines and a cornerstone of modern engineering. At its core, the design is straightforward: it consists of a large circular disc, the wheel, which is firmly attached to a smaller central rod called the axle. When one part turns, the other part turns with it. This simple combination is the basis for countless inventions that shape our world.

The primary purpose of a wheel and axle is to make work easier. One way it achieves this is by making the movement of heavy objects much (21) __________. Imagine trying to drag a heavy box across the floor. Now, imagine putting that same box on a cart with wheels. The cart rolls smoothly because wheels reduce the resistance, or friction, between the object and the ground.

When the large wheel is turned, the narrower axle also rotates, but with greater force. This principle is perfectly demonstrated by a common doorknob. A small, gentle turn on the knob (the wheel) generates enough force in the axle to move the latch inside the door. Because of this, you can open a heavy door with very little effort. This multiplication of force is a key advantage.

Examples of the wheel and axle are everywhere. From the wheels on a car to the swivel casters on an office chair, the system allows for smooth and efficient movement. The main goal is to reduce friction, allowing objects to roll instead of being scraped across a surface. Even a simple screwdriver works on this principle, where the handle is the wheel and the metal shaft is the axle.

The wheel's large circumference means it travels a greater distance than the axle in a single turn. (22) __________ provides a mechanical advantage, making it a powerful tool. So critical is this invention that (23) __________ could we imagine our modern world without it. (24) __________, the wheel and axle is a simple but brilliant innovation that has been fundamental to human progress for thousands of years.

Organ transplantation stands as one of humanity's most extraordinary medical triumphs. It represents the pinnacle of surgical skill, demanding meticulous precision, unwavering dedication, and seamless teamwork from medical professionals. These life-saving procedures offer a second chance to patients grappling with organ failure, offering a renewed promise of life. Each is a testament to scientific ingenuity, pushing medical boundaries. Beyond the impressive technology, lies the profound bravery of both the patients and the physicians who embark on these high-stakes journeys.

[I] In 2004, Vietnam aimed to join nations capable of complex organ transplants. The nation's medical community, particularly at Military Hospital 103 in Hanoi, dreamed of Vietnam's first successful liver transplant. This was no small feat. [II] It seemed insurmountable, given the country's nascent surgical techniques and immense resource needs at the time.

Despite the daunting challenges, a dedicated team of Vietnamese surgeons and medical staff committed to this monumental task. They trained abroad with international experts, mastering intricate procedures. [III] Meticulous planning, scenario simulations, and protocol refinement consumed countless hours back home. This period was characterized by immense pressure and unwavering resolve. Their mission: save a life, elevate national medical capabilities, and demonstrate unparalleled bravery and perseverance.

Finally, on November 27, 2004, the culmination of years of preparation arrived. Inside the operating theatre at Military Hospital 103, the highly skilled team worked tirelessly for many hours. Every critical cut, stitch, and decision demanded incredible focus and coordination. [IV] The atmosphere was charged with tension and shared purpose as they meticulously replaced the diseased liver with a healthy one. When the complex surgery was successfully completed, it marked a monumental milestone not only for the patient, but for Vietnam's entire medical landscape, proving a miracle was possible.

This landmark achievement deeply resonated across Vietnam, inspiring new medical professionals and boosting healthcare confidence. The transplant's success paved the way for advanced surgeries and organ transplant development, significantly improving patient outcomes. For 14-15 year olds, this story vividly illustrates medicine's profound human impact. It showcases how dedication, continuous learning, and teamwork lead to life-changing breakthroughs, sparking interest in pursuing medical careers as doctors, nurses, or researchers who might one day perform their own miracles.