A collocation is two or more words that often go together. These combinations just sound "right" to native English speakers, who use them all the time. On the other hand, other combinations may be unnatural and just sound "wrong".
Why learn collocations?
- Your language will be more natural and more easily understood.
- You will have alternative and richer ways of expressing yourself.
- It is easier for our brains to remember and use language in chunks or blocks rather than as single words.