2010年08月13日(北美機經)
1. VENUS和EARTH的大氣和水。
主要說的水討論為啥它們有相同大氣組成，現在VENUS卻沒有水了。
主要原因是VENUS離太陽更近（有題）原本 VENUS是有好多水的，但是由於太陽光照慢慢蒸發掉了。
這裏考到辭彙illuminated，反正選BRIGHT。
然後因為蒸發就越來越多二氧化碳，然後溫室效應，溫度就很高。
2. 有聲電影的發展。
這個大家應該很熟吧，但是好像又不完全相同。
一開始也是愛迪生大叔發明了個東西，給電影配聲。但是呢，科技不成熟，換DISK 啥的時候就不同步了。
考了simultaneous這個詞，那當然選 AT THE SAME TIME 啦.後來發展到樂隊伴奏什麼的。
3. wheel cart 的發展.一開始是 sled，一個拖板，沒輪子的（有圖）。
後來慢慢在美索不達米亞發展起來的。
但是呢，wheel工具一開始並沒有運用在平時生活中，而是一些ceremony啊什麼的。
再後來，這種wheel還運用在戰爭中。
The origin of the wheel and cart 輪子與推車的起源
The origin of the wheel is unknown, but once it was invented, knowledge of the wheel spread rapidly throughout the Mediterranean and Asian world. Wheeled vehicles made the movement of goods much easier. The earliest known examples of wheels are from Mesopotamia and date from about 3500 to 3000 bc. The cart or wagon, pulled by humans or animals, was the first wheeled vehicle. Today, animal-drawn carts are still used in many countries, primarily to move freight but sometimes to transport people. The horse-drawn chariot, a faster version of the cart, became an important instrument of warfare because it could overpower enemy soldiers quickly. The chariot appeared in Mesopotamia around 2000 bc, and its use later spread to Egypt, Persia, Greece, Rome, and other ancient civilizations.
While the invention of the wheel was important to the development of transportation in Europe and Asia, the wheel was unknown to the ancient civilizations of North and South America. People in these areas used pack animals or dragged goods on crude sledges. Europeans brought the wheel to the New World as they began to settle there in the 16th century.
Horse-drawn stagecoaches and covered wagons played a critical role in the development of the United States and Canada in the 1800s. Conestoga wagons, covered wagons that could carry loads weighing up to 7 tons, were used extensively in the settlement of the western United States.
A Sumerian (Erech) pictograph, dated about 3500 BC, shows a sledge equipped with wheels. The idea of wheeled transportation may have come from the use of logs for rollers, but the oldest known wheels were wooden disks consisting of three carved planks clamped together by transverse struts.
Spoked wheels appeared about 2000 BC, when they were in use on chariots in Asia Minor. Later developments included iron hubs (centerpieces) turning on greased axles, and the introduction of a tire in the form of an iron ring that was expanded by heat and dropped over the rim and that on cooling shrank and drew the members tightly together.
The use of a wheel (turntable) for pottery had also developed in Mesopotamia by 3500 BC.
The early waterwheels, used for lifting water from a lower to a higher level for irrigation, consisted of a number of pots tied to the rim of a wheel that was caused to rotate about a horizontal axis by running water or by a treadmill. The lower pots were submerged and filled in the running stream; when they reached their highest position, they poured their contents into a trough that carried the water to the fields.
The three power sources used in the Middle Ages—animal, water, and wind—were all exploited by means of wheels. One method of driving millstones for grinding grain was to fit a long horizontal arm to the vertical shaft connected to the stone and pull or push it with a horse or other beast of burden. Waterwheels and windmills were also used to drive millstones.
Because the wheel made controlled rotary motion possible, it was of decisive importance in machine design. Rotating machines for performing repetitive operations driven by steam engines were important elements in the Industrial Revolution. Rotary motion permits a continuity in magnitude and direction that is impossible with linear motion, which in a machine always involves reversals and changes in magnitude.

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