4+4又1/2*6/7/9/14分之5--(1又5/6+1又11/18)=4+9/2×6/7×1/9×14/5-（1又15/18+1又11/18）=4+(9/2×1/9)×（6/7×14/5）-3又4/9=4+1/2×12/5-3又4/9=4+1又1/5-3又4/9=4+1又9/45-3又20/45=1又34/45...