Answer:
Use me if you really want to see inside someone
I begin your sentences.
I have a neck but no head arms but no hands. What am I?
What starts with an 'e' and ends with an 'e' but only has one letter?
I am the beginning of the end and the end of time and space. I am essential to creation and I surround every place.
No matter how little or how much you use me, you change me every month.