An Interrogative Pronoun (question word) is a word we use in an information question (as opposed to a yes/no questions).
The most common question words in English are:
WHO is only used when referring to people, when we want to know the person.
- Who is the new student?
- Who are your friends?
WHERE is used when asking about a place or location, when we want to know the place).
- Where is the nearest Post Office?
- Where do you live?
WHEN is used when asking about a time or an occasion, when we want to know the time.
- When does the mall open?
- When is your birthday?
WHY is used when asking for a reason, when we want an explanation.
- Why do we need to do so much homework?
- Why are you always late?
WHAT is used when asking for specific information, when we want to know the thing.
- What is his name?
- What is your favorite color?
WHICH is used when asking for specific information and you have a limited choice, when we have to choose between alternatives.
- Whichis your favorite color – red or blue?
- Which day of the week is more tiring?
HOW (by itself) is used to describe the way that something is done when we want to know the manner.
- How do you turn on the computer?
- How do engines work?
HOW, when used with a quantifier gives us other, more specific expressions:
How much – refers to a quantity of an uncountable nouns, or a price.
- How much time will this take?
- How much is the shirt in the window?
How many – refers to a quantity of countable nouns.
- How many beers did you drink last night?
- How many people live in this NY?
For more on How many vs. How much look at this page
How often – refers to the frequency with which something happens.
- How often do you travel?
- How often does she study?
How far – refers to the distance between two places.
- How far is the school from your house?
- How far is the bus stop from here?
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