We discuss here the complementarity effect of rewriting services in a language-translation Web service work-flow. The communication mediated by the machine translation service includes mistranslations and changed meanings, which are caused by the quality of the machine translation. To reduce these problems, we propose service reallocation and assemblage of the rewriting service by humans at each stage of the workflow. We set up two rewriting service allocation patterns: 1) a reallocation pattern as a previous rewriting process, and 2) a reallocation pattern as a follow-on rewriting process, for workflows consisting only of machine translations. A team of human judges provide multiple assessments of adequacy and fluency of sample sentences that are translated from English to Japanese using each pattern. Results indicated that the Japanese rewriting task as a follow-on rewriting service provided greater fluency than an English rewriting task as a previous rewriting service, with nearly equal adequacy.