Machines in the home have a short history. Sewing machines, washing machines and tumble dries are common enough today, but a hundred years ago few people could even imagine such things. However, inventors have designed and built a wide range of household machines since then. In most cases the inventor tried to patent（申请专利）his machine, to stop anyone copying it. Then he tried to produce a lot of them. If the machine became popular, the inventor could make a lot of money.
In 1790 the first sewing machine was patented. The inventor was an Englishman called Thomas Saint. There was nothing to match his machine for forty years, and then someone built a similar device. He was a Frenchman, Bartelemy Thimonier. However, neither of these early machines worked very well. It wasn’t until 1846 that an inventor came up with a really efficient sewing machine. He was an American, Elias Howe and his machine was good enough to beat five skilled sewing women. He didn’t make much money from it, however. The first commercially successful sewing machine was patented by Isaac Singer five years later.
Today, we take washing machines for granted, but there was none before 1869. The revolving drum（旋转桶）of that first machine set a pattern for the future, but it was crude by today’s standards. The drum was turned by hand, and needed a lot of effort. Eight years passed before someone produced an electric washing machine. The world had to wait even longer for a machine to dry clothes. The first spin-drier was another American invention, patented in 1924; but it was 20 years before such machines were widely used.
It was yet another American, called Bissell, who introduced the carpet sweeper. He patented the original machine back in 1876. It didn’t pick up dirt very well, but it was quicker than a dustpan and brush. Thirty-six years later, even the carpet sweeper was old-fashioned: modern homes now have a vacuum cleaner（吸尘器）with an electric motor to suck the dust.
72. Whose sewing machine could do as much as,or even more than the work of five skilled sewing women?
A. Thomas Saint’s. B. Bartelemy Thimonier’s.
C. Elias Howe’s. D. Isaac Singer’s.
73. According to the article, modern inventors __________ .
A. follow the pattern of the first revolving drum but improve it much
B. only imitate (模仿)the first washing machine
C. power the first ever-made washing machine by electricity
D. have to wait for the first spin-drier for a long time
74. The underlined word “crude” in the sentence “but it was crude by today’s standards” probably means __________ .
A. useless B. ugly-looking C. rough D. not skillfully made
75. The article mainly tells us about __________ .
A. the great inventors in the world
B. the important inventions in the world
C. the short history of household machines
D. the importance of the machines used in the home