干葡萄要经过发酵，直到没有糖分存留，葡萄酒才不会有甜味。
The dried grapes are allowed to ferment until there is no sugar left and the wine is dry.
红茶是经过发酵的。
它们是绿茶、红茶、乌龙茶和花茶。没有经过发酵的绿茶颜色跟原来茶叶的颜色一样。
They are green tea, black tea, Oolong tea and scented tea. Without fermentation, green tea keeps the original color of the tea.
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