To decide whether to use the subject or object pronoun after the words “than” or “as”, mentally complete the sentence.
• Sonali is as smart as she/her.
— If we mentally complete the sentence, we would say Sonali is as smart as she is. Therefore, she is the correct answer.
• Rina is taller than I/me.
— Mentally completing the sentence, we have Rina is taller than I am.
• Graham would rather talk to her than I/me.
We can interpret this sentence in two ways:
– Graham would rather talk to her than (talk) to me.
– Graham would rather talk to her than I would (talk to her).
The meaning of a sentence can change considerably, depending on the pronoun you choose.
Although for most people the “than me” (using object pronoun) version sound more natural than the “than I” (using subject pronoun) version, the previous runs the highest risk of being considered wrong. It’s because the “than I” version has been around longer and seems more grammatically correct. The “than I” version is falling out of favor and now sounds a bit stilted though.
Evidently, the dilemma between the “than I” and “than me” is not clear cut. So, the best thing to do is to consider your audience (listeners/readers). In formal situations, it would be best to stick with the “than I” (subject pronoun). Otherwise, you may need to be prepared to fight your corner. 🙂