Can we survive only on raw, leafy vegetables/grass? Discuss.

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks whether humans can survive solely on raw leafy vegetables or grass.

2. **Composition of Raw Leafy Vegetables and Grass**: Raw leafy vegetables and grass primarily consist of cellulose, which is a complex carbohydrate.

3. **Digestive Capabilities of Humans**: Humans lack the necessary enzymes to digest cellulose. This means that when we consume raw leafy vegetables or grass, our bodies cannot break down cellulose into usable energy.

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