4 adjectives to describe expatiates

To understand this, one should hear the French-Canadian expatiate upon the superiority of the wooden to the metal bridge.

The cynic expatiates on painful thingsthe blot on life's beauty, the shadow on its glory, the pitiful ending of its brave showsonly to gibe and mock.

With my own ears I have heard a great fair-headed lad expatiate to all his neighbours on the pretty ways of his little daughter who is eight years old.

He then is taken to hear a sermon, where for his special benefit, I suppose, the preacher expatiates on the glorious field of Bunker's Hill, foretells England's decline, and generously promises our countrymen a home in America when they are quite "used up."

4 adjectives to describe  expatiates