There is also a propensity to claim that personal pronouns are a signal of emphasis, as illustrated from Wallace’s discussion: The nominative personal pronoun is most commonly used for emphasis. The emphasis may involve some sort of contrast. In such instances, two subjects are normally in view, though one might be only implied. This contrast is either of kind (antithetical) or degree (comparison). For example, in “He washed and she dried,” the contrast is comparative (both people doing the dishes).
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