WH questions in French

Language: French
Level: Beginner
Topic: WH- questions/Mots interrogratifs

When you want to do a question, your basic words are the WH questions. 
When? What? Where?, etc.
Today, this post is about these type of questions in French, which are called 'Mots interrogatifs'

I'll give you some examples of these questions: 

What is that? - C'est quoi ça?

When is the party? - Quand c'est la fête?

Where are you? - Oú es-tu? /Tu es oú?

Who is him? - Qui est lui?

Why are you doing this? - Pourquoi tu fais ça?

How can I do it? - Comment peux-je le faire?

How much is it? - C'est combien?

How much does it cost? - Combien ça coûte?

To whom do I give these flowers? - À qui je donne cette fleurs?

Unfortunately, the word "quel" in French, has number and genre. Which means that it can be singular or plurar, masculine or femenine.

The base is "quel" (which is masculine & singular), then you'll add:
-le (femenine & singular)
-s  (masculine & plural)
-le (femenine & plural

So, when you want to say:
Which book?
First, you need to determine the genre of the word book, which is masculine: le livre. Then, you have to see if it is singular or plural. Therefore, you have to add "quel"
Quel livre?

The same will happen when you translate the following questions:

Which story? - Quelle histoire?
story- l'histoire (f)

Which books? - Quels livres?
Which stories? - Quelles histoires?