Answer:
They have not flesh, nor feathers, nor scales, nor bone. Yet they have fingers and thumbs of their own.
What word is a plural, but when you add an "S" to the end, it becomes singular?
You can see nothing else, When you look in my face, I will look you in the eye, And I will never lie.
My life can be measured in hours, I serve by being devoured. Thin, I am quick. Fat, I am slow. Wind is my foe.
They're up near the sky, on something very tall. Sometimes they die, only then do they fall.
What covers its face with its hands, speaks no language, yet most known what it's saying?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?