天山-4-12

for the farmer who takes care to keep them cool,(providing them with high-energy feed,and milking them regularly,hostein cows are producing) an average of 2275 gallons of milk each per year.

c:provided with high-energy feed,and milking them regularly,hostein cows are producing

e:provided with high-energy feed, and milked regularly,hostein cows will produce

答案是e,可我觉得a也很有道理呀

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4-12 http://forum.chasedream.com/dispbbs.asp?BoardID=23&ID=83292