Grass fed products have proved to be healthier and more nutritious.
2019年12月六级真题（第三套）阅读 Section B
In the grass fed system, farmers are also not subject to the wildly fluctuating milk prices of the international commodity market.
2019年12月六级真题（第三套）阅读 Section B
The rest is feed-lot confined and fed grain and corn.
2019年12月六级真题（第三套）阅读 Section B
Though advocates portray grass fed products as a win-win situation for all, they do have downsides.
2019年12月六级真题（第三套）阅读 Section B
To recover the energy, the gas is fed back over the calcium oxide.
2018年12月六级真题（第二套）听力 Section C
柯林斯高阶英汉双解学习词典释义
Fed is the past tense and past participle of feed .
N-COUNT
(美国安全局、联邦调查局、酒精、烟草与枪支管理局等)联邦机构工作人员
The feds are federal agents, for example of the American security agency, the FBI, or of the Bureau of Alcohol, Tobacco, and Firearms.
英英词典释义
Noun
1. any federal law-enforcement officer
2. the central bank of the United States; incorporates 12 Federal Reserve branch banks and all national banks and state charted commercial banks and some trust companies;
"the Fed seeks to control the United States economy by raising and lowering short-term interest rates and the money supply"