第二篇：       Just by looking at a penguin, it is clear to see that their bodies have been specially adapted for swimming. Theyhave developed a streamlined body shape that reduces drag when they are in the water. Their wings (called “flippers”on penguins) and feet also serve a purpose. Their flippers function like propellers when underwater, allowing them tomove forward and increase their speed. While swimming, their feet get tucked away near the tail to be used to navigatethrough the water. All penguin bodies are covered in oily feathers, which allows the water to flow smoothly over theirbodies, thus reducing drag. However, this is not the only thing a penguin’s body can do.     Back in 2012, scientists discovered the mystery behind how Emperor Penguins rocket through the water. First,penguins can trap air under their feathers. It was discovered that when Emperor Penguins fluff these tiny feathersunderwater, they release bubbles that act like a lubricant to reduce drag. With this extra boost, these penguins can doubleor triple the speeds at which they usually travel, which can help to propel individuals onto land or help with avoiding apredator. In addition, a penguin’s blood helps them to stay underwater for longer. The blood can carry extra oxygenaround the body, allowing oxygen to be stored, and therefore helping them to breathe underwater for enough time tohunt.    Not only have these birds evolved and adapted perfectly to being in the water, but they have also developedincredibly successful swimming techniques too. For long journeys, many penguins use a technique known as“porpoising”. This is when a penguin will propel forward out of the water, allowing them to catch a breath as they doso. When penguins do this, they can easily increase their speed by a substantial amount.
【題組】46. Which of the following is the most appropriate title for this article?
(A) Why do penguins live in extremely cold places?
(B) How do penguins feed their chicks?
(C) How do penguins swim so well?
(D) Why do penguins love to eat fish and krill?