# 21.2 PRONOMES
"21.2" pronomes
Why are sentences so easy to understand? How do we compress our ideas into strings of words and, later, get them out again? Typically, an English sentence is built around a verb that represents some sort of act, event, or change:Jack drove from Boston to New York on the turnpike with Mary.
As soon as you hear such a thing, parts of your mind become engaged with these sorts of concerns related to driving:

He changed the liquid from water to wine.
The liquid has changed its composition from what it was "at" some previous time. In English we use prepositions like "from," "to," and "at" both for places in space and for moments in time. This is not an accident, since representing both space and time in similar ways lets us apply the selfsame reasoning skills to both of them. Thus, many of our language-grammar "rules" embody or reflect some systematic correspondences — and these are among our most powerful ways to think. Many other language-forms have evolved similarly to make it easy for us to formulate, and communicate, our most significant concerns. The next few sections discuss how the "pronomes" we mentioned earlier could be involved in processes we use to make both verbal and nonverbal "chains of reasoning."