12．文中共有10处语言错误，每句中最多有两处．错误仅涉及一个单词的增加、删除或修改
增加：在缺词处加一个漏字符号（
），并在其下面写出该加的词．删除：把多余的词用（\）划掉．
修改：在错的词下画一横线，并在该词下面写出修改后的词．
注意：（1）每处错误及其修改均仅限一词；
（2）只允许修改10处，多者（从第11处起）不计分．
Never shall I forget the writing class presented to our English teacher today．Yesterday Mr．Wang，our English teacher，told us that many other teachers will visit the writing class．We were looking forward to it．It struck us as a big surprise was that Mr．Wang，who was used to be punctual，didn't appear when the school bell rang．The teachers sit behind the class were quite puzzling．We were quite worried about him，wondering what have happened to him．Five minutes late，Mr．Wang showed up in front of us!On the blackboard was the writing titles："When Our English Teacher Was Late for Class．"Only then we realize that he had intended to be late!
