Đề ôn thi Đề thi vào lớp 10 Trường Phổ thông Năng khiếu môn Tiếng Anh - Mã đề PTNK-45

Chameleons are famous for their ability to change color. Many people believe they do this to hide from predators by matching their surroundings. However, the primary reason for this change is not camouflage. The truth is more complex and fascinating, involving communication and reactions to their environment.

The secret to this ability lies beneath the chameleon’s transparent outer skin. They have special cells called chromatophores, which are responsible for the color change. These cells are organized into several different layers. This system allows for a wide range of colors and patterns to be displayed.

Each layer of chromatophores has a different function. The top layer, for instance, (21) __________ yellow and red pigments. Beneath that, another layer reflects blue and white light. By expanding or shrinking these different cells, a chameleon can mix these colors. They can alter their appearance very (22) __________ when necessary.

So, why do they change color? The reasons are varied, (23) __________ on the chameleon’s mood, the temperature, or the light. For instance, a dark color might mean the chameleon is cold and trying to absorb more heat. Bright colors can be a way to communicate with other chameleons. These factors directly affect how the cells react.

In conclusion, the chameleon's color change is a sophisticated form of expression. While it can help with camouflage, it is more accurately a visual language. It helps the chameleon survive and interact with its world, and this adaptation continues to (24) __________ an important role in its life.

Street food is a vibrant and essential thread in the fabric of urban life worldwide. From bustling markets in Bangkok to late-night stalls in New York, it offers an authentic taste of local culture, often affordably. More than just a meal, it represents a dynamic culinary landscape, a quick glimpse into a city's soul. However, alongside its undeniable charm and cultural significance, persistent questions often linger about food safety and hygiene, creating a nuanced debate: is this beloved cultural treasure also a potential health risk?

In Vietnam, this debate resonates particularly strongly. Vietnamese street food, celebrated globally for its incredible diversity and complex flavors, has recently garnered prestigious international recognition. Cities like Hanoi and Ho Chi Minh City now boast numerous street food vendors and humble eateries highlighted in the Michelin Guide, elevating these everyday delights. Dishes like phở, bún chả, and bánh mì are not just meals; they are iconic symbols of Vietnamese heritage, attracting tourists and locals alike.

For many young people, especially teenagers in Vietnam, street food isn't just about cultural heritage; it's an integral part of daily social life. [I] Gathering with friends after school to share bánh tráng nướng, or enjoying savory xiên bẩn skewers from a roadside cart, are common and cherished experiences. [II] These moments are filled with laughter, shared stories, and the distinct flavors that define youthful memories. It’s a convenient, delicious, and budget-friendly way to connect and unwind, often becoming the backdrop for countless adolescent adventures.

Yet, beneath this appealing surface lies genuine concern about health and safety. [III] The very nature of street food – prepared and served in open-air environments with varying access to sanitation and temperature control – raises legitimate questions. [IV] This prompts consumers and authorities to constantly evaluate the balance between accessibility, taste, and public health.

Ultimately, the question of whether street food is a cultural treasure or a health risk isn't simple. It's undeniably both. Its cultural value, economic accessibility, and social significance are immense, especially in countries like Vietnam where it's deeply ingrained. However, acknowledging and addressing inherent health risks through improved hygiene practices, consumer awareness, and appropriate regulation is crucial. Enjoying street food responsibly means appreciating its unique charm while being mindful of safety, ensuring this beloved tradition continues to thrive healthily.