This puzzle is called Literal Thinking.
1.
Man
------
Board
Ans: Man Overboard
2.
Stand
-------
I
Ans: I Understand
3. |r|e|a|d|i|n|g|
Ans: Reading between the lines
4.
cycle
cycle
cycle
Ans: Tricycle
6.
0
--------
M.Phil
Ph.D
Ans: two degrees below zero
7.
knee
------
light
Ans: Neon Light
(knee-on-light)
8.
ground
---------------
feet feet feet
feet feet feet
Ans: six feet underground
9. ecnalg
Ans: backward glance
10. Death...Life
Ans: Life aftr Death
11.THINK
Ans:think BIG
& the last one is real fun
12
ababaabaabbaaababaaab
Ans: Long time no 'C :-D