The problem is of course the vagueness in natural languages caused by the complexity of its grammar and the unstated contextual nature of it all.

"The black truck driver ran through the red light."

Is the truck black or is the truck driver black?

Is the driver driving, or is he running on foot?

Is the red light a traffic indicator, or is it a just a beam of red light?

Teaching a computer to figure out the intended interpretation here is a monumental task, and teaching the people to understand how their use of language is actually very easy to misunderstand is even harder.