请你修改下面短文，共有10处语言错误，每句中最多有两处．每处错误仅涉及一个单词的增加、删除或修改．增加：在缺词处加一个漏子符号（∧）并在其下面写出该加的词．删除：把多余

Question

请你修改下面短文，共有10处语言错误，每句中最多有两处．每处错误仅涉及一个单词的增加、删除或修改．
增加：在缺词处加一个漏子符号（∧）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．
People used to communicate with each other through letters and public phones．So nowadays they use mobile phones and the Internet instead of．This change in communication have good effects on our works and life．Comparing with letters and public phones，mobile phones and the Internet are fast and much more convenient．If you missed your grandmother，you just take out your phone and say"hello"to him．And she will be happy to hear your voice．If you want to place order with a foreign company，you can e-mail the message．It'll be minutes after you get their reply．

Answer 1

People used to communicate with each other through letters and public phones．So nowadays they use mobile phones and the Internet instead of．This change in communication have good effects on our works and life．Comparing with letters and public phones，mobile phones and the Internet arefast and much more convenient．If you missed your grandmother，you just take out your phone and say"hello"to him．And she will be happy to hear your voice．If you want to place∧order with a foreign company，you can e-mail the message．It'll be minutes after you get their reply．
详
1．So改为But 考查连词．前后两个单句之间是转折关系而非因果关系，用连词but．
2．去掉of 考查词语用法．instead意为"替代，顶替"，是副词，instead of意为"（用…）代替…"，是介词短语，此处应是：替代，顶替．
3．have改为has 考查主谓一致．主语change是单数形式，谓语动词也应用单数形式has．  
4．works改为work 考查名词．work是不可数名词，没有复数形式．
5．Comparing改为Compared 考查过去分词．mobile phones and the Internet与compare之间是动宾关系，用过去分词短语Compared with letters and public phones作状语．
6．fast改为faster 考查形容词比较级． and是并列连词，它前后连接两个相同的语法成分，faster和much more convenient都是形容词比较级作并列表语．
7．missed改为miss 考查动词时态．本文讲述的是一般事实，用一般现在时态．
8．him改为her 考查代词．her指代grandmother．
9．加an 考查冠词．是可数名词，单数形式前加不定冠词表示泛指，因其读音以发元音开头，用不定冠词an．  
10．after改为before 考查连词．It+be+一段时间+before-clause此句型中的"一段时间"通常用long，years，weeks，days，hours，minutes等词语表示．主句中的谓语动词为肯定形式时，意为"过一段时间才…"；主句中用will be时，before从句中常用一般现在时．