“案件”发生在一个星期四的下午,风和日丽,并无异常之处,但却显得和往日与众不同——同学们都在摆弄着为下节课精心准备的磁铁,忙得不亦乐乎。可过了一会儿,小王同学却焦急万分地问大家:“你们有没有看到我的磁铁?我的磁铁丢了。”可以看到,小王同学因着急,额头上渗出了细密的汗珠。但同学 “Case ” took place on a Thursday afternoon, the wind was sunny, there is no exception, but it is different from the past - the students are playing with the magnet carefully prepared for the next class, busy Exhilarating. But after a while, Xiao Wang students are anxiously asked you: “You have not seen my magnet? My magnet is lost.” Can see, Wang students anxiously, the forehead leaking out of the fine Sweat beads. But classmates