A collocations dictionary allows us to learn how words can be combined in English to say what we mean, and say it naturally.
I would go as far as saying that For Better English is a unique online tool to explore the combination of words together.
So far, our options to check out whether our collocations were correct were limited to running a Google Fight or simply typing the phrase to check in the search box of Google and draw our own conclusions from the number of hits we got.
I hope you find For Better English useful.