Unlike English, Chinese does not distinguish between singular and plural, so nouns are simply abstract in number, with context determining whether something is singular or plural.
But when you have to specify a certain number of something, you combine the number itself with a measure word, followed by the noun, eg. 一匹马(a horse), 两只笔(two pens), 三本书(three books).
Below is a comprehensive list of Chinese measure words and what they are used to count.
