Đề ôn thi Đề thi vào lớp 10 Trường THPT Chuyên KHXH môn Tiếng Anh - Mã đề KHXH-29

The life cycle of a frog is a remarkable journey of transformation, known as metamorphosis. This process begins with a large cluster of eggs, called frogspawn, laid in or near water. From each jelly-like egg hatches (35) __________ tiny aquatic creature called a tadpole. At first, it looks more like a small fish than a frog, possessing a long tail for swimming and lacking any limbs.

During its initial stage, the tadpole is perfectly adapted for life underwater. It breathes using special organs called (36) __________, which extract oxygen directly from the water, just as fish do. Its primary diet consists of algae and other small plant matter, which it scrapes from surfaces with its tiny mouth. The tadpole spends its days swimming actively, growing bigger and stronger in preparation for the dramatic changes that are to come.

Gradually, the transformation begins. First, back legs start to sprout, and a little later, front legs appear. (37) __________, the tadpole's body begins preparing for life on land. As these limbs grow, the tadpole starts to (38) __________ the appearance of a miniature frog, although it still has its long, powerful tail. This intermediate stage is often called a 'froglet'.

Internally, even more significant changes are occurring. The gills that were essential for underwater life begin to disappear as a pair of lungs develops. Its body starts (39) __________ its long tail for energy and nutrients, causing it to shrink. A biologist once explained that the tail (40) __________ gradually absorbed, not simply dropped off. This absorption is a crucial part of fueling the final, energy-intensive stage of metamorphosis.

Finally, the tail vanishes completely. If the tadpole (41) __________ this final stage successfully, it would not be able to survive out of the water. With its new lungs, strong legs, and no tail, the young frog is now fully equipped for a life on land. It can hop away from the water's edge to hunt for insects, a very different diet from what it ate as a tadpole. The transformation from an aquatic herbivore to a terrestrial carnivore is, (42) __________, complete.

Have you ever thought about the impact your daily life has on the planet? Every time you turn on a light, charge your phone, or travel to school, you are contributing to what is known as your 'carbon footprint'. This term represents the total amount of greenhouse gases, primarily carbon dioxide (CO2), released into the atmosphere because of your activities. These gases trap heat, leading to global warming and climate change. Understanding your carbon footprint is the first step towards making more environmentally conscious decisions.

On a larger scale, the concept of a carbon footprint applies to countries as well. As Vietnam's economy continues to grow rapidly, there has been a significant increase in its national carbon emissions. This growth, while positive for development, presents a major environmental challenge. In response, the Vietnamese government has implemented policies like the National Strategy on Climate Change, which aims to promote a low-carbon economy. This strategy encourages industries to adopt cleaner technologies and pushes for the development of renewable energy sources, balancing economic progress with environmental protection.

So, how does this relate to you, a teenager in Vietnam? Your individual choices add up. Think about your daily routine. Do you travel to school by motorbike, bicycle, or electric bus? Do you leave your computer on all night? The food you eat also matters. Locally grown produce has a smaller carbon footprint than imported goods that travel thousands of kilometers. All of these small decisions define the size of a teenager's personal carbon footprint and their overall impact on the environment.

The good news is that reducing your carbon footprint doesn't require drastic changes. Simple habits can make a big difference. For instance, unplugging chargers and electronics when they are not in use can cut down on 'phantom' energy consumption. Choosing to walk, cycle, or use public transport instead of private vehicles reduces emissions significantly. Furthermore, being mindful of waste by reducing single-use plastics and recycling properly helps conserve resources and energy.

Ultimately, tackling climate change is a collective effort. While government policies and corporate actions are crucial, the power of individual choice should not be underestimated. By understanding and actively working to reduce your carbon footprint, you are not just making a small personal change. You are becoming part of a global movement of young people who are taking responsibility for the future of our planet. Your choices today will shape the world of tomorrow.