* No written records: For much of human history, languages were only spoken, not written down. This leaves us with no direct evidence of what was said.
* Language changes constantly: Languages evolve over time, so even if we had records from thousands of years ago, it's likely they wouldn't be easily understood today.
* Limited archaeological evidence: While archaeology can tell us about ancient cultures, it rarely provides direct information about their spoken language.
What we can do:
* Linguistic reconstruction: Linguists can use the relationships between modern languages to reconstruct what ancient languages might have been like. However, this is a complex process with a lot of uncertainty.
* Archaeological evidence: Sometimes, archaeological finds like inscriptions or pottery markings can provide hints about ancient languages. But this is often limited and can be difficult to interpret.
* Genetic evidence: Research into human genetics can help us understand how languages spread and evolved, but it can't tell us what people actually said.
In summary: We can't definitively say what languages people spoke in the past, but we can use a combination of methods to make educated guesses and learn more about the history of human language.