Update Shell Programming.md

Author: xuchaoyong

Shell Programming.md

@@ -7,7 +7,10 @@ sed -n '5,7p'
 
 ```
 
-##2. print the specific colume
+##2. print the specific colume in three methods
 ```
 sed -n '5p' hello | awk 'BEGIN {FS=","} {print $4}'
+head -n 4 hello | tail -n 1 | cut -d " " -f 3
+sed -n 4p hello | cut -d " " -f 3
+#There are two way to get the specific column with cut or awk. Also, head and tail to get the certain line.
 ```