He is a strict teacher, but all the students like him. I don't know why.
如图,正方形ABCD中,点E、F分别在BC、CD上,△AEF是等边三角形,连接AC交EF于G,下列结论:①BE=DF,②∠DAF=15°,③AC垂直平分EF,④S△CEF=2S△ABE,其中正确的结论有( )