Đề ôn thi Đề thi vào lớp 10 Trường Phổ thông Năng khiếu môn Tiếng Anh - Mã đề PTNK-145

Silk is one of the world's most luxurious and prized natural fibers, known for its incredible softness, shine, and strength. For thousands of years, this delicate material has been used to create beautiful clothing and textiles. The journey of silk begins not in a factory, but with a tiny creature: the silkworm. The entire creation of this fabric is a fascinating natural transformation, which has been perfected by humans over many centuries.

The process starts when a female silk moth lays its eggs. Once hatched, the larvae, or silkworms, are fed exclusively on fresh mulberry leaves. They eat almost constantly and grow very quickly. After several weeks, each silkworm begins to spin a protective casing around itself. This casing, known as a cocoon, is produced by the silkworm from a single, continuous filament of raw silk secreted from its glands. This raw silk is harvested from the completed cocoon.

(21) __________ the cocoons are carefully collected, they are boiled in water. This step is crucial because it softens the gummy substance that holds the cocoon together, making it possible to unwind. Skilled workers then carefully locate the end of the filament and unwind the cocoon, revealing a single continuous thread, (22) __________ can be several hundred meters long. This part of the production requires a gentle and steady hand.

These individual silk filaments are too thin to be used alone, so several are twisted together to (23) __________ a stronger, thicker yarn. This yarn can then be dyed in a variety of brilliant colors. Afterward, the colored yarn is woven into fabric on a special machine called a loom. It takes many threads and a significant amount of time to produce even a small piece of silk cloth. This entire process requires great skill and patience from the weavers.

The final product is a smooth, lightweight, and surprisingly strong fabric that is highly sought after for high-end fashion and home furnishings. Despite the development of synthetic fibers like nylon and polyester, silk (24) __________ still highly valued for its unique combination of comfort and elegance. The long journey from a tiny cocoon to a finished piece of fabric makes every meter of silk a true work of art.

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.