How do you say “Don't pretend that you don't like me!” in Korean?

= 나(를) 안 좋아하는 척하지 마! [na-(reul) an jo-a-ha-neun cheo-ka-ji ma!]

How do you say “You, too!”in Korean?

= (__terms of address_)도요! [(__terms of address_)-do-yo!]

How do you say “This cat is like a tiger.” in Korean?

= 이 고양이는 호랑이 같아요. [i go-yang-i-neun ho-rang-i ga-ta-yo.]

How do you say “I was going to the movies, but I changed my mind.” in Korean?

= 영화관에 가려고 했는데, 마음이 바뀌었어요. [yeong-hwa-gwa-ne ga-ryeo-go haen-neun-de, ma-eu-mi ba-kkwi-eo-sseo-yo.]

How do you say “That's a good idea!” in Korean?

= 좋은 생각이에요! [jo-eun saeng-ga-gi-e-yo!]