She is an expert in nursing.

He is a rationalist, making all decisions based on logic and facts.

This system is too irrational to understand.

I am surprised at the irrationality of this system.

Please leave a message on the message board.

I am studying natural language processing at university.

Natural language processing is the technology that allows computers to understand and generate human language.

Creating a new recipe is a series of trial and error.

He repeated trial and error to create a new recipe.

He ignored my opinion by coercion.