Enlist four peculiar characters of birds.

Explanation

### Step-by-Step Solution:

1. **Modified Forelimbs**: Birds have forelimbs that are modified into wings. This adaptation allows them to fly, which is one of the most distinctive characteristics of birds.

2. **Feathered Body**: The body of birds is completely covered with feathers. Unlike other animals that have skin, birds possess feathers which serve various functions including insulation, waterproofing, and aiding in flight.

3. **Pneumatic Bones**: Birds have bones that are pneumatic, meaning they contain air cavities. This adaptation makes their bones lighter, which is beneficial for flight as it reduces overall body weight and minimizes the friction experienced while flying.

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