Jespah has already pointed this out. 1-3 aren't sentences, they're sentence fragments.
A sentence makes sense on its own, in order to make sense more needs to be added.
Become a saviour to the people by eating cornflakes.
To cause unwholesome impact just leave the door open when you're having a ****.
Because of his fascination with the girl Ponderer was banned from A2K.
Now they're sentences.
Jespah has already answered this, every post since then is redundant, (including this one.)