任务型读写。 阅读下面短文，根据所读内容在表格中的空白处填入恰当的单词。 注意
题型：阅读理解
问题：
| 任务型读写。 阅读下面短文，根据所读内容在表格中的空白处填入恰当的单词。 注意：每个空格只填一个单词。 | ||||||||||||
| From the beginning of human history, people have used oils from seeds and nuts. Most of the time these oils are used as food, especially in cooking. But sometimes they have other uses. For example, oils are used in paint and in cleaning products like soap. Oil is separated from seeds by using pressure. A machine called a press is often used. The first step in pressing the oil from seeds is to crush the seeds between two stones. The crushed seeds are then put into a cloth bag and the bag is hung up. Some of the oil will flow out of the bag and can be collected. But some oil will remain in the crushed seeds inside the bag. The easiest way to get the rest of the oil out is to place heavy rocks on the crushed material. Another method is to place several cloth bags on top of each other in a box. Then a long wooden stick is used to slowly push a heavy cover down on the bags. Great pressure is produced in this way. Much greater pressure can be produced by using a machine, a hydraulic jack (液压千斤顶). The greater the pressure, the more oil win be produced. Small presses are important in areas where electricity or gasoline cannot be used. They are also a good way to test if a local market for oil exists. Small batch presses can be made of local materials. Their cost is low. They are not difficult to operate. And they are easy to repair. The small presses produce good quality oil. But the work is hard. And getting all the oil from the seeds can be difficult. If there is a large supply of seeds, then hand-operated presses may not be enough to support a business. Large, powered presses that can operate all day are needed. | ||||||||||||
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