On the old-time farm in America there were chickens and turkeys. There were also cows, pigs, and other livestock. But there very few machines. Most of the work was done by the entire farm family with the help of a “hired” man. Sometimes extra laborers were needed in busy seasons. Horses provided 79 percent of the power used, human labor 15 percent, and machines only 6 percent.
Today all that has changed. On many modern farms machines now supply 96 percent of the power, human labor 3 percent, and horses 1percent.Modern farms are enterprising businesses which keep only the livestock that can pay its way. The children go to school by bus every morning, the parents work on the farm or in the house, and hired help is seldom needed. Their work has been replaced by a whole army of farm machines.
Farmers in the machine age also use the new fertilizers, new sprays, new feeds, new hybrid seeds, and other helps developed by farm sciences. As a result the farmers are able to produce more food with less labor. This means fewer but larger farms and fewer but more prosperous farmers.
51.In olds, most of the work on a farm was done by______.
A.all the farm family B.livestock
C.farm machines D.both A and B
52.From the first paragraph, we learn that in old days the most important farming power was_______.
A.livestock B.farmers C.machines D.extra laborers
53.On today's farms, the chief reason why livestock is still raised would probably be________.
A.that farmers' conventions are difficult to be given up
B.that farmers want to gain more profit
C.that farmers have to do so
D.that farmers' work has been replaced by machines
54.On modern farms, farmers need mostly all the followings EXCEPT _______.
A.farm science B.seeds C.fertilizers D.hard work
55.In the last sentence of paragraph 3,"fewer but larger farms and fewer but more prosperous farmers" means ________.
A.hired help is seldom needed
B.productivity on the farms has been raised greatly
C.productivity on the farms has fallen sharply
D.more food is never needed