Instructions: Given a text, write a compressed version of it in a single sentence.
Input: Based on the sparse evidence available, linguists theorized about the earlier languages that had given rise to those attested. In other words, based on what they knew about a group of languages which were documented, they tried to imagine the language that they sprang from.
Output:
Evidence shows, linguists theorized about the earlier languages that had given rise to those attested. Based on what they knew about a group of languages , they tried to imagine the language originated.