关键词: 软模, 软同态, 软正合序列

Abstract: By using module theory and the basic properties of soft modules, we discussed the decomposition properties of soft homomorphism. Firstly, we defined a single  soft homomorphism of  soft modules and soft exact sequence. Secondly, 
we proved that every soft homomorphism could  be decomposed into  the composition of an epimorphism and a monomorphism. Finally, we discussed the basic properties of soft exact sequences, and gave equivalent conditions 
for several kinds of simple soft modulus sequence to be exact, and constructed a new  soft exact sequence by using two soft exact sequences.

Key words: soft module, soft homomorphism, soft exact sequence