What number when divided in half becomes zero?

There is an English word that can be used up to four times in a row without modifying the spelling and form a valid grammatical sentence.

Do you know what word is that?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?

Take number 1000 and then add 20 to it.
Now add 1000 one more time.
Now add 30.
Now add 1000 one more time.
Now add 40.
Now add 1000 one more time.
Now add 10.

What is the total?

Rearrange the letters in "new door" to make one word.

I am never scared but became petrified and can’t live in a house but would die to make one. What am I?

Make a sentence consisting of three words that have the whole alphabet.

Can you name four days which start with the letter 'T'?

Which flower has two lips?

Can you make a six-letter word using the letters N, A and B ?