∵四边形ABCD是平行四边形
∴AB=CD AB∥CD
易得:△AEF∽△CDF
∵AE:EB=1:2
∴ AE:AB= 1:3
∴相似比k=AE:CD=AE:AB =1:3
∴△AEF与△CDF的周长比为1:3
∴S△AEF:S△CDF=1:9
∵S△AEF:S△AFD=EF:DF=k=1:3
设:S△AEF=x 则S△AFD=3x S△CDF=9x
S△ACD=S△AFD+ S△CDF=3x+9x=12x
S△AFD=3x=6
x=2
S△ACD=12x=24
S△ABC=S△ACD=12
S四边形BEFC=S△ABC-S△AEF=24-2=22