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Hexose is a type of monosaccharide, mainly used as an energy source.

This is a kind of flower.

This problem is simply a matter of not having enough time.

The source of this river is halfway up the mountain.

This feature can be used easily.

He mainly eats vegetables.

We are using LED bulbs for energy saving.

We should use more renewable energy.

The fountainhead of this river is at the top of the mountain.