What grammatical error exists in: "A few weeks ago, my friend asked me to recommend hotels and restaurants in Tuscany, since I have visited Italy more than her."?

The sentence presents an error related to the comparison being made, specifically in how the pronouns are used. The correct form should convey a proper comparison between the speaker and the friend regarding their experiences in Italy.

In this context, the phrase "more than her" is incorrect because it lacks the necessary clarification when comparing the experiences of two people. To make a proper comparative statement regarding who has visited Italy more, the sentence would need to use a subject pronoun, resulting in the corrected phrasing "more than she has" or "more than she." This ensures that the sentence adheres to proper grammatical structure by explicitly comparing the speaker's experiences against the friend's.

Utilizing "her" in this comparison, which is an object pronoun, causes confusion and undermines the clarity of the intended meaning. Therefore, the pronoun should be positioned correctly within its comparative form to maintain grammatical integrity and coherence.