It became a commonplace to say that he was put to death for an error of judgment.
They just live their own old, quiet, and commonplace life, thought Natasha.
"Life is remarkably commonplace, if you think about it," I countered.
His work is a kind of commonplace book kept without scientific discrimination.
Proceeding upon such lines as these, the Jews wove together their Midrashic homilies or sermons where, though we may find much that seems commonplace, there are illuminating parables and proverbs, metaphors and similes, the whole affording admirable examples of the contemporary thought and culture, both of the writers and - what is often overlooked - the level of their hearers or readers.