Big or Large?

As an ESL learner, I think that most of people are wonder the differences between the words Big and Large, so let's try to figure them out.

First, I'd like to show their similarities; both of them mean" of more than average size/amount/weight/height, etc."  Then, neither 'big' nor 'large' can be used with uncountable noun.  For example, you can describe that "May has a big/large house" but you cannot say that "What a big/large rain" (What a heavy rain is correct)

Now I will give the definition of 'big' from Oxford Advanced Learner's Dictionary.http://www.oxfordadvancedlearnersdictionary.com/dictionary/big

Big means large in size, degree, amount,etc, and in informal way, it also means older:
ex: My big brother is John.

it can also be used to describe something that is important or serious:
ex: Leo has made a big mistake.

Then we check the word 'large'.  It is more formal than 'big' and should be used in writing unless it is in an informal style.  It is not usually used to describe people, except to avoid saying 'fat'.

To sum up, though the definitions of 'big' or 'large' are the same in Chinese, they still have slight differences and are used in various ways in English. If we don't understand the correct and exact way of word use, it is good for you to look up the Learner's Dictionary.


Reference:
http://www.bbc.co.uk/worldservice/learningenglish/radio/specials/1837_aae/page24.shtml