Bonjour Hemlata,

Elle a cinq crayons -> Elle n'a pas cinq crayons

Take a look at the link below: 

Ne ... pas = Not - with simple tenses (French Negations)

I hope this is helpful.

Bonne journée !

Bonjour Hemlata,

The main point of the lesson here is to understand that when the affirmative statement uses the indefinite article "un" (elle a un crayon), if the sentence is using the negative form then it will have "ne...pas de/d' " (elle n'a pas de crayon). 

Remember: When you want to emphasise the meaning of ONE (un/une) - not just a/an - as in He doesn't have ONE car, but TWO, you will keep un/une in the negative sentence - but here it doesn't mean no/any.

If there is a number (and not an indefinite article) in the affirmative statement (elle a cinq crayons) and you simply want to focus on the fact that she doesn't have five of them, then it will become "elle n'a pas cinq crayons / elle n'en a pas cinq".

I hope this is helpful.

Bonne journée !