Sudden trouble speaking during a conversation can be an indicator of stroke.
If you’re talking with them, and they suddenly seem as if they can’t understand the meanings of the words they’re using, this is definitely a troubling sign.
They may also have trouble understanding even basic words if they’re having a stroke.
And a stroke victim will often seem confused all of the sudden.
If the person is drooling and doesn’t seem to notice, this is another common sign of stroke.
Someone having a stroke can have sudden facial numbness, maybe even have some unusual drooping of one side or the other.