Dan Smith has given a great answer as usual.

Hello Ei Shwe Zin :) Space can be used in both countable and non-countable ways. "There's still some space in the living room," is a non-countable example. On the other hand, space in the sense of, e.g. a parking space is countable: "You can go out and count that there are 5 empty spaces." So whether space is countable depends on whether it is used to refer to some undetermined area or volume, or whether it is used to refer to a specific designated block of space. We see a similar example of countable and non-countable when speaking of space on a page: "There was some empty space at the bottom of the page." (non-countable) vs. "Type only one space (not two) after each period." Hope, it was helpful. Best regards, Anastasiia

"Space" can be a countable noun meaning a particular area. Quite often, an uncountable noun X also has a countable meaning of "a piece of X" or "a chunk of X" or "a separated portion of X." Here are some examples. A hundred years ago, maps of the world still had spaces marked "unexplored," but aerial and satellite photography have filled in the uncharted spaces. We have adopted the coding standard of indenting loops by four spaces. In mixing concrete, enough sand must be used to fill the spaces between the gravel, and enough cement to fill the spaces between the grains of sand. "There are vast spaces in other lands as well as in this one. Asia has wilds as lonely as America." "Of the blank spaces in the record of Rembrandt's career, none is so long or so inexplicable as that which begins with his return from Amsterdam to Leyden in 1624."