Some

 Some 

Some are used in a positive sentences. Some can be used for objects countable and uncountable nouns. Some are not used in negative sentences or questions.

for example :

•  We bought some coffee.
•  I have some friends.
•  My sisters buy some books. 

            But some can also be used to offer something (offer) and demand (request), we need to put some words in a sentence asked.

for example :

• Would you like some oranges? (offer)  
• Can I have some tea? (request) 

"some " can also be used in sentences like the place, at a time and certain things.

example :

• I'm sure I will meet him some day.
•  I met him in some place.

source of : http://www.kursusmudahbahasainggris.com/2013/10/pengertian-penggunaan-dan-contoh.html