It is vital "to be conscious of a reader" when writing, but few chances exist to analyse a reader's perception of a learner's sentence. Therefore, in a foreign student upper level composition class, to develop the viewpoint of the reader, I gave a task where the learner had to describe sight information in words, and the reader had to read it and draw a picture. First I will introduce the procedure of the activity, and descriptions by learners which became clearer through this activity. Then, I will talk about notable points in the Japanese instruction that appeared from how learner's sentences reached the reader. Furthermore, I will report the conclusions from the questionnaire results to the learner, and the significance of this activity.