“我非常了解我的朋友”，这是一种（）知识。

Last Sunday afternoon my friends and l were walking in Zhongshan Park when we suddenly heard someone calling for help．A girl fell into the lake and she was in danger．One of my?friends and I iumped into the lake and swam towards the girl．When she was pulled out of it．she had stopped breathing．I had?learned sonic knowledge about first aid at sch001．So I tried to start her breath by using the mouth-to-mouth way．My friend phoned?the First Aid Centre．Within ten minutes the girl began to
breathe again and the doctors from the First Aid Centre arrived．
The girl Was saved．They all said that what I did was right．
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