They would have been almost pure hydrogen — the primary ingredient of thermonuclear fusion, which makes a star shine.

它们可能曾经几乎完全是由氢元素构成的，氢元素是热核融合的主要原料，正是这种反应让星星放出光芒。

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He has retained his fascination with chocolate's primary ingredient and Africa, the heart of cocoa production, ever since.

从此之后，他就迷恋上了这种巧克力的主原料和可可的主产地——非洲。

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What's the primary ingredient, regardless of what beverage you've ordered?

无论你点了何种饮料，里面的主要成分是什么呢？

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Siluria converts methane, the primary ingredient in natural gas, into liquid fuels and chemical intermediates.

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Sure, the water comes from natural aquifers 200 feet below the surface and the primary ingredient is 100% organic estate-grown winter wheat.

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Ms. Jackson late last year delayed a decision on whether to tighten the government's limits on ground-level ozone, a primary ingredient in smog.

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