Riddles!! 10 points anyone?!?!?!?

[Daddio]

1) The more you take of me, the more you leave behind. What am I?
2) When you have me, you want to share me. If you share me, you don't have me. what am I?
3) Which phrase is stated correctly: 18 + 19 is 36, or 18 + 19 are 36.

 

[bball lover]

1)i have no idea
2)a secret
3)18+9 IS 27

 

[lazywolf62791]

footsteps/footprirts
blame
neither. 18+19=37

 

[Sunny Gray McRae]

1)Food
2)Gum
3)Neither it's 37

 

[Joshua]

1) footsteps/ footprints?
2) blame
3) neither: 18+19= 37 not 36

-edit-
you guys are right- 2 is a secret