With her indeed he not infrequently fell into discussion upon physics, the theory of agriculture, and especially philosophy; philosophy was Agafea Mihalovna’s favorite subject.
Here, in the country, with children, and with Darya Alexandrovna, with whom he was in sympathy, Levin was in a mood not infrequent with him, of childlike light-heartedness that she particularly liked in him.
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You’d be surprised how infrequently I get something I truly want."
Kiera Cass -- The Elite
Gradually, their visits became shorter and more infrequent.