She said that he was very earnest, and had a beautiful nature.
Fortunately for him she had on the other side Lord Faudel, a most intelligent middle-aged mediocrity, as bald as a Ministerial statement in the House of Commons, with whom she was conversing in that intensely earnest manner which is the one unpardonable error, as he remarked once himself, that all really good people fall into, and from which none of them ever quite escape.
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Show samples from other sources
Both sides were deeply in earnest, even passionate.
She has a casual, go-with-the-flow personality and doesn’t appreciate his earnestness.