What is collocation?

A collocation is a combination of words that are commonly used together; the simplest way of describing collocations is to say that they ‘just sound right’ to native English speakers. Other combinations that may mean the same thing would seem ‘ unnatural’. Collocations include noun phrases like ‘ stiff wind’ and 'weapons of mass destruction’, phrasal verbs such as 'to get together’ and other stock phrases such as 'the rich and famous’

It is important to learn collocations, because they are important for the naturalization of one’s speech. Besides, they broaden one’s scope for expression.