QUESTIONS WORDS

http://www.grammar.cl/Notes/Question_Words.htm

WHO

WHO is only used when referring to people. (= I want to know the person)

Who is the best football player in the world?
Who are your best friends?
Who is that strange guy over there?

WHERE

WHERE is used when referring to a place or location. (= I want to know the place)

Where is the library?
Where do you live?
Where are my shoes?

WHEN

WHEN is used to refer to a time or an occasion. (= I want to know the time)

When do the shops open?
When is his birthday?
When are we going to finish?

WHY

WHY is used to obtain an explanation or a reason. (= I want to know the reason)

Why do we need a nanny?
Why are they always late?
Why does he complain all the time?

Normally the response begins with "Because..."

WHAT

WHAT is used to refer to specific information. (= I want to know the thing)

What is your name?
What is her favourite colour?
What is the time?

WHICH

WHICH is used when a choice needs to be made. (= I want to know the thing between alternatives)

Which drink did you order – the rum or the beer?
Which day do you prefer for a meeting – today or tomorrow?
Which is better - this one or that one?

HOW

HOW is used to describe the manner that something is done. (= I want to know the way)

How do you cook paella?
How does he know the answer?
How can I learn English quickly?

With HOW there are a number of other expressions that are used in questions:

How much – refers to a quantity or a price (uncountable nouns)

How much time do you have to finish the test?
How much is the jacket on display in the window?
How much money will I need?

How many – refers to a quantity (countable nouns)

How many days are there in April?
How many people live in this city?
How many brothers and sister do you have?

How often – refers to frequency

How often do you visit your grandmother?
How often does she study?
How often are you sick?

How far – refers to distance

How far is the university from your house?
How far is the bus stop from here?
https://www.englishclub.com/vocabulary/wh-question-words.htm

WH Question Words

We use question words to ask certain types of questions (question word questions). We often refer to them as WH words because they include the letters WH (for example WHy, HoW).

question word	function	example sentence
what	asking for information about something	What is your name?
what	asking for repetition or confirmation	What? I can't hear you. You did what?
what...for	asking for a reason, asking why	What did you do that for?
when	asking about time	When did he leave?
where	asking in or at what place or position	Where do they live?
which	asking about choice	Which colour do you want?
who	asking what or which person or people (subject)	Who opened the door?
whom	asking what or which person or people (object)	Whom did you see?
whose	asking about ownership	Whose are these keys? Whose turn is it?
why	asking for reason, asking what...for	Why do you say that?
why don't	making a suggestion	Why don't I help you?
how	asking about manner	How does this work?
how	asking about condition or quality	How was your exam?
how + adj/adv	asking about extent or degree	see examples below
how far	distance	How far is Pattaya from Bangkok?
how long	length (time or space)	How long will it take?
how many	quantity (countable)	How many cars are there?
how much	quantity (uncountable)	How much money do you have?
how old	age	How old are you?
how come (informal)	asking for reason, asking why	How come I can't see her?