Your version:
The purpose of the study is to apply the English songs to vocabulary teaching to improve the efficiency of primary students in memorizing the vocabulary and provide the teachers with a efficient method to teach vocabulary, according to the characteristics of primary students.
My version:
In light of the psychological characteristics of primary students, using (the technique of using) English songs to teach vocabulary will improve the pupil's efficiency in memorizing vocabulary and will also provide the teacher with an effective method of teaching vocabulary,