If eleven plus two equals one, what does nine plus five equal?

Lifeless eyes on my smiling face and watch your child's sleeping place. In their dreams they hold me tight. What am I?

How can you write nineteen in a manner that if we take out one, it becomes twenty?

How many letters are in the alphabet?

What have one eye but still cannot see?

I know there are two methods by using three time the same number with a plus(+) operator , you can make sum as 60.

One of them is 20+20+20.

whats the other way ?

I have four wings but can't fly.
I express no emotions.
I am found on the exact spot every time you look.
I keep toiling away with a little sound.

Do you know what am I?

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

They do not possess flesh or feathers or scales or bone
But still, they are blessed with fingers and thumbs of their own.

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?