There are many specific activities of small intestine like...
the much part of food is digested here...
digested food is absorbed in small intestine and energy is sent to cells.
may I know who you are.
girl or a boy.
it's alright.'s alright....
no offense.
The most important activity of small intestine is absorption of food. It has small projections known as Villi which is 0.3 mm in length which has a rich supply of blood capillaries absorbs the food and sends to the cells. Villi also increase the surface area of small intestine for absorption

The digestion process gets over in the duodenum(upper part of small intestine) and the non digestible food matter goes to the large intestine