Dinda:alvin ,areyou free next saturday afternoon? alvin: i am, have no plan yet. why? dinda:i have a surprise for you. will you come to my house at 4 pm? alvin:a suprise for me? i'm curious.sure i'd love to come, but will you tell me what it is about? dinda:no, i want hope you like my surprisealvin: i see. by the way, are you willing to join my group
dinda:what kind of group? alvin:i have a study group named sky high. there are ten members,who are our schoolmates and we discuss english, math, and science. we study online together on the weekends. dinda:it sounds intersting. yes, i'm wiling to join please add ny number. alvin :o.k . who are talking in the dialog?