对勾上一个圈是什么CAD符号?这个以及右边这个符号分别是什么意思,请说具体点有什么作用?

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，在该行右边横线上划一个对勾（P）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：在错词下面划一横线，在该行右边横线上写出正确的词。
注意：原行没有错的不要改。
Three men were fishing when the angel appeared in the boatwith them. The first man got over his shock and politely said tothe angel, “I’ve suffered by back pain for years. Can you helpme?” The angel touched his back, and he had recovered.The second man pointed to his glass and asked if the angelcould cure her poor eyesight. The angel touched his eyes,but he could see everything clearly.The angel then turned to the third man, threw up his handsin fear. “Don’t touch me!” he cries. “I’m on disability pay!I don’t want to be a normally person!”