Ⅱ. 至少选用下列单词中的五个，写一个完整的段落。
summary, selfish, hidden, prove, effect, librarian, enemy, naughty

The librarian in our school is a warm-hearted lady who is always patient with students, but she can't stand selfish behaviors. Last week, a naughty boy took a popular science book from the shelf and hid it in a hidden cabinet, because he didn't want other students to read it. When the librarian found the book was missing, she decided to prove who did it. She checked the library's monitoring system and soon found out the truth. The naughty boy felt ashamed and apologized to everyone, realizing his selfish act had a bad effect on others.

选取题目中至少五个指定单词，围绕合理场景创作符合八年级英语水平的连贯段落，确保单词用法准确、语句通顺自然。