There are many who argue that corn ethanol should replace fossil fuel gas as the primary source for running cars.

许多人认为，玉米乙醇应该取代化石燃料气体，成为汽车的主要燃料。

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Parallel rails had long been used in mining operations to move bigger loads, but horses were still the primary source of power.

在采矿作业中，平行铁轨早已被用来运送大件的货物，但马匹仍然是主要的运输工具。

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Wood, the primary source of heat for homes and industries and also used in the iron industry as processed charcoal, was diminishing in supply.

木材是家庭和工业的主要热源，也以加工木炭的形式用于铁工业，它的正在减少。

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That's not the only place but that's a primary source of it.

这不是唯一的出处,但是最主要的来源

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

You see the lactose of course from milk, and then when you get down to the cellulose, and we're talking about starches and then fiber gets involved in here too, then cereals and vegetables become the primary source of these.

你们知道乳糖来自于乳类,当你研究纤维素的时候,以及我们在这里所说的淀粉和纤维,他们最主要的来源是谷类和蔬菜

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

This is probably your primary source of income, so make the most of it.

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Ads -- which are included in the redesign -- are Facebook's primary source of income.

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The book focused on access to alternative asset classes as the primary source of endowment alpha.

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