题目内容
Without transportation, there could be no trade. Without trade, there could be no towns and cities. Towns and cities are traditionally the 16 of civilization. Therefore, transportation helps make civilization 17 . Throughout most of the prehistoric period, people lived by hunting, fishing, and 18 wild plants. They had no beasts of burden, wheeled vehicles, or roads. People traveled 19 and carried their infants and belongings strapped to their backs or heads. Loads too heavy for one person to carry were strapped to a pole and carried by two people. 20 , people learned that they could drag loads along the ground on sledges. During late prehistoric times, people began to build sledges with runners. When people developed agriculture and began to establish 21 settlements, trade between settlements started to develop, which created a need for better 22 of transportation. The donkey and the ox, which had been tamed for food products and farm work, helped 23 this need. The use of donkeys and oxen as beasts of burden enabled people to 24 heavier loads than they could before. People also began to develop water transportation during prehistoric times. They built rafts of such 25 as logs or reeds. Later, people learned 26 to make dugouts and canoes. People paddled these early craft with their hands or propelled them with paddles or 27 . The wheel was invented about 3500 B.C. and sailboat about 3200 B.C. Wheeled vehicles and sailing vessels 28 transportation. But the speed of transportation improved only 29 over the centuries. Inventors produced the first engine- 30 vehicles during the late 1700’s and the early 1800’s. This development marked the beginning of a revolution in transportation that has continued to the present.
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“It’s not so much what my husband says,” a tearful wife confides, “as the way he says it. Why does he have to yell at me”
Without transportation, there could be no trade. Without trade, there could be no towns and cities. Towns and cities are traditionally the 16 of civilization. Therefore, transportation helps make civilization 17 . Throughout most of the prehistoric period, people lived by hunting, fishing, and 18 wild plants. They had no beasts of burden, wheeled vehicles, or roads. People traveled 19 and carried their infants and belongings strapped to their backs or heads. Loads too heavy for one person to carry were strapped to a pole and carried by two people. 20 , people learned that they could drag loads along the ground on sledges. During late prehistoric times, people began to build sledges with runners. When people developed agriculture and began to establish 21 settlements, trade between settlements started to develop, which created a need for better 22 of transportation. The donkey and the ox, which had been tamed for food products and farm work, helped 23 this need. The use of donkeys and oxen as beasts of burden enabled people to 24 heavier loads than they could before. People also began to develop water transportation during prehistoric times. They built rafts of such 25 as logs or reeds. Later, people learned 26 to make dugouts and canoes. People paddled these early craft with their hands or propelled them with paddles or 27 . The wheel was invented about 3500 B.C. and sailboat about 3200 B.C. Wheeled vehicles and sailing vessels 28 transportation. But the speed of transportation improved only 29 over the centuries. Inventors produced the first engine- 30 vehicles during the late 1700’s and the early 1800’s. This development marked the beginning of a revolution in transportation that has continued to the present.
Americans eat ______ vegetables per person today as they did in 1910.
______ we can hope for is to avoid complete failure in the coming game with that strong team.
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