Q:

"He saddens" - Describes he becomes sad?

I want to describe in writing that someone suddenly becomes sad. For example, John and Mike are chatting in a restaurant. John explains what happened in his life. Initially he was speaking normally. Then, he becomes sad while describing a event, later tears comes out from his eyes.  Now, how do I say he becomes sad or how I say his face becomes sad (before tears fall out from his eyes)?
Can I write "John saddens"?

A:

The usual construction is "He IS saddenED." That is, it is a predicate adjective, as opposed to a predicate.
Another construction is (e.g.), "The DEATH saddens HIM." In this construction, the reference to the person is as an object, which is to say in the passive.
"He saddens" (nominative) just doesn't work.

