The above is the comparison between pens and pencils: the pen above is written by a junior, the pencil in the middle is written by a sophomore, and the pen below is written by a sophomore. It can be seen that although the first-year students write well, they still make mistakes and can only cross; The bottom one also travels frequently, and he uses correction fluid; In the middle is a small classmate on a business trip, but it can be wiped.