此题要求改正所给短文中的错误。对标有题号的每一行作出判断：如无错误，在该行右边横线上画一个勾（√）；如有错误（每行只有一个错误），则按下列情况改正：
此行多一个词：把多余的词用斜线（\）划掉，在该行右边横线上写出该词，并也用斜线划掉。
此行缺一个词：在缺词处加一个漏字符号（∧），在该行右边横线上写出该加的词。
此行错一个词：在错的词下划一横线，在该行右边横线上写出改正后的词。
注意：原行没有错的不要改。
I received your letter was dated April l6 the day                        76．            
before yesterday．All of our family greatly delighted to                     77．            
learn how you are getting along very well with your                           78．            
lessons．Time passes quickly．After dozens of days, you’ll                 79．            
finish the middle school．What pleases us most is that you                  80．            
do very well to make up your mind to enter for the college                 81．            
entrance examination this summer．What wonderful it is !                  82．            
Dad, as well as Mom and I, is with you．We wished                          83．            
you to make better use of your time．The full preparations                 84．            
you make, the surer of success you’ll certain be．                               85．