To know the age,depth,height,length,wideth,time etc,How+adjective is used.The bellow
structure is used,
How +adj. +to be +subject? For example
He is 20.
How old is he?
The pond is 12 feet deep.
How deep the pond is?
To know about quantity ,how much is used and to know about the number,how many is used. The structure is
How much/many +noun +aux. verb+subj.+verb+ext?
He ate as much as rice he could.
How much did he eat?
He will buy ten eggs.
How many eggs will he buy?
To know the adverb of frequency or degree,how +adv. is used.
He can run very fast.
How fast can he run?
He comes here twice a week.
How often does he come here.
How +adv. +aux. verb+subj. +verb +ext?
To know the cost or price of anything,how is used.
The pen cost me 15 taka.
How much did the pen cost me?
Della sold her hair at 50 dollars.
How much did della sell her hair?
How much +aux. verb+subj. +verb +ext?
Besides we can use the bellow structure,
what is the price/cost of+ noun or noun phrase? For example
What is the cost of the pen?
What is the price Della's hair?
In order toknow someone physically ,one can use the structure
How +to be +noun or pronoun?
How are you?
How is your mother?
But for expressing greetings or to introduce with anyone ,then we can use
How do you do?
Read the bellow question:
He failed for his laziness.
Why did he fail?
They came home to chop wood.
Why did they come home?
To know the reason of any occurance ,why is used.the structure is