SHELL

grep lines after match

$ grep -A1 text

-AX tells grep to display 'X' amount of lines after line of match. 
Use -BX to do the same but before.

grep line after match

Include -A flag to add lines after match and -B flag to add lines before
grep match -A 3	#display match line and 3 after lines
grep match -B 2 #display match line and 2 lines before

grep third line after match

Include -A flag to add lines after match
grep match -A 3	#display match line and 3 after lines