English proficiency has become essential for Japanese people in today’s globalized society. However, since the structure of the Japanese language is very different from that of English, it has proven difficult for Japanese people to create natural and fluent English sentences without specialized training. We developed a support system for English composition using a new method which addresses this issue. The main characteristic of the system is the use of a dictionary of similar sentence patterns. This dictionary was developed by defining a new distance measurement between sentences that emphasize expressions at the end of a sentence in a Japanese text due to the head finality of Japanese. Our experiment revealed that in terms of fluency of translation, higher scores were obtained with this system, in comparison with the singular use of a word dictionary. Also, in terms of both adequacy and fluency, the average values with this system exceeded those with traditional support systems for English composition considered in this study.