And with this, a five year old catapulted back in time, say 10,000 years in West Asia or Southern Europe, encountering two people, would make perfectly intelligible sentence that wold be understood by all. Assuming all the people who were listening were at least reasonably savvy about language and a little patient. This is because a handful of words, including Who, You, Two, Five, Three and I exist across a range of languages as close cognates, and can be reconstructed as similar ancestral utterances in ancestral languages.
It's like an elephant and a mammoth meeting up in the Twilight…