(1)1m3=1000dm3;(2)1L=1dm3; (3)1L=1000ml;(4)81cm3=81ml; (5)700dm3=0.7m3;(6)560ml=0.56L; (7)2.3dm3=2300cm3.故答案为:1000,1,1000,81,0.7,0.56,2300.