I shave every day, but my beard stays the same. What am I?

No matter how little or how much you use me, you change me every month. What am I?

I welcome the day with a show of light, I stealthily came here in the night. I bathe the earthy stuff at dawn, But by noon, alas! I'm gone.

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

I am the largest in my family of fifty.
The youngest of our family lives separately from the rest of the family and so do I.
I am regarded as harsh and tough.
I am so large, you cut me in two equal halves,
each half would still be larger than the second largest member of the family.
Who am I?

I am a word of 12 alphabets.

* Alphabets 12, 4, 7, 2, 5 : Eastern beast of burden
* Alphabets 1, 8, 10, 9 are street made famous by Sinclair Lewis.
* Alphabets 11, 3, 6 are past.

On whole it means a person suffering from delusions of greatness.

What Is it ?

Take one out and scratch my head, I am now black but once was red. What am I?

A finger goes in me. You fiddle with me when you're bored. The best man always has me first. What am I?

When you stop to look, you can always see me. But if you try to touch me, you can never feel me. Although you walk towards me, I remain the same distance from you. What am I?

I’m tall when I’m young, and I’m short when I’m old. What am I?