问题：这句话不符合英语句子中的平行结构.while是连词,连接的两个句子必须形式上一致,意思上表示对比.
这句话里while前主语是humorous,宾语是junior students；while后主语是senior students,宾语是pop novels.所以结构上不对称.
应该改为：
1.Humorous stories are popular among junior students,while popular novels are preferred by senior students.
OR 2.Junior students like humorous stories,while senior students perfer reading popular novels.