Here we have a verb, leaning, preceded by an auxiliary verb, was. Verbs with auxiliaries are never as sharply focused as verbs without them, because the former indicate indefinite time, whereas the latter suggest a given instant. The novelist’s goal is to let the story unfold as it happens, to keep the reader in the moment—the “ongoing present.” One thing that will help you do that is to use verbs that tell readers what’s happening right now.
The example sentence, therefore, would be more focused if you dropped the was and said “She leaned. . . .”
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