What Am I Riddles

Question: Take my first and make it my last, now I happened in the past.

What am I?

Question: You can rest on my pad without touching the keys.
I will sing all month long as long as you pay your fees.

What am I?

Question: I give you a family of three:

One is sits down, and will never get up.
The second eats as much as is given to him, yet is always hungry.
The third goes away and will never return.

What are they?

Question: "Good morning!" - I appear again! Time for breakfast - I`m long as F*** Its dinner time - I`m crouching down Supper time approaches - I`m on my tippy toes "Good night!" - ...gone again... What am I?

Question: What goes up and down the stairs without moving?