Assignment 3: The difference between "big" and "large"

I used online concordancers and dictionary to find the answer. The results are as follows:
(1)When "BIG" is a asjective, it can define the degree、volume of object.
ex:How big the birthday cake is!
(2)BIG also can describe the state of people.
ex:You're big boys now.
(3)When "LARGE" is a asjective, it can explain the total of individuality.
ex:The concert drew a large audience
(4)Large was used to writing composition, because it a formal word than "big".
ex:He vomited large amounts of blood-stained sputum.
In the end, BIG and LARGE are different, so I need using them carefully