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

What Word am I Looking For ?

John named his first son Alpha, second Beta, third Charlie and fourth Delta. What is the fifth son's name?

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

There is a family that live in a round house. The two parents go out for a movie and leave a babysitter to watch their son. They come back and the kid was not there. Some one kidnapped him. The maid said she was cleaning in a corner. The cook said he was making pizza. The babysitter said she was getting a board game. Who kidnapped him.

You can hear me, but you can't touch or see me.

What am I?

I can turn polar bears white.
I can make anyone dance.
I can make everyone cry
I can make your hands clap
I can make you thin.
I can make you smile.
I can make you smile

Can you guess the riddle?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

Prove that twice of ten is the same as twice of eleven.

What can go through glass without breaking it?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?