Teacher Lia is smarter than me. Teacher Lia is more gorgeous than my friend.

Hello Hyeon, Yeong. Your sentences are clear and grammatically correct. You used comparative adjectives very well. Keep practicing making comparisons like this, and I will continue to support you and guide you to be even more confident in using English correctly. I'm proud of you, always.

~ T. Lia

Teacher Lia is smarter than me.

>> CORRECT or

>> Teacher Lia is smarter than I. 

Teacher Lia is more gorgeous than my friend.

>> CORRECT