The document discusses two theories about the origin of language:
1. The Bow Wow Theory proposes that early humans imitated animal sounds to communicate, like saying "bow wow" to refer to dogs. Over time, these imitative sounds evolved into early words.
2. The Gesture Theory argues that one of the earliest forms of communication involved using hand gestures and signs, which later developed into spoken words by imitating the mouth and tongue movements associated with gestures. For example, pointing up with the hand also involves raising the tongue. Both theories suggest that language originated from imitating physical actions or sounds in the environment.