Two friends were walking through the desert． During the journey they had an argument， and the（1） 　　boy slapped the shorter one in the face． The shorter boy was hurt． But without （2） 　　anything， he wrote in the sand， "Today my best friend slapped （3） 　　in the face．"

They kept on walking （4） 　　they found a pond． And they decided（5） 　　a bath there． But the shorter boy got stuck （6） 　　the mud and started to sink． He cried， "Help! Help!"Luckily， he was pulled to （7） 　　by his friend． After that． he carved on a stone， "Today my best friend saved my life．"

The taller boy asked him． "After I hurt you， you wrote it in the sand， but now you carved it on the stone．Why？"

The shorter boy replied， "When someone （8） 　 B 　you， you should write it in the sand from which the wind can erase it （9） 　　． However， when someone does something （10） 　　for you，you should carve it on a stone from which the wind can never erase it．"

（1）A． tall	B． taller	C． tallest
（2）A． saying	B．say	C．said
（3）A．I	B． my	C． me
（4）A．till	B． after	C． because
（5）A．to take	B．took	C． take
（6）A．on	B．in	C．at
（7）A．safe	B．safely	C．safety
（8）A． hurt	B．hurts	C hurting
（9）A．easily	B．easy	C．easier
（10）A．harmful	B．bad	C．good