现在的小学毕业考试试卷都改为电脑阅卷了。电脑阅卷说明规定,在试题中写错字,既不能用改正液涂,又不能用改正贴覆盖,写错了只能划掉。但写错的字太多,划掉太多,写不下了怎么办?这时,我想到发明一种两用笔,它的外形和一支普通的黑色签字笔差不多,只是多了两个按钮:一个按钮是黑色的,按一下,有黑色签字笔头出来正常地书写。另一个按钮是黄色的,按一下,一个类似于笔头的部件就出来了,部件里面装 Now the primary school graduation exam papers are replaced by computer scoring. Computer marking instructions stipulate that the wrong words in the test questions, both can not be corrected with liquid coating, but also can not be used to correct the paste cover, the wrong can only be crossed out. However, the wrong words too much, crossed out too much, can not write how to do? At this time, I think of inventing a dual-use pen, its appearance and an ordinary black pen almost, but more than two buttons : A button is black, click, black signature written out to write normally. Another button is yellow, click, a similar to the tip of the parts came out, the parts inside