Collocation?

teacherJapanWhen you use the word 'problem', you wouldn't use 'important' to describe it?

Oh, but I would if it were appropriate. Why not?

teacherJapanWhen I look it up in a collocation dictionary, it says 'problem' is often used with 'serious, major, big.'

Collocation dictionaries can be thorough but not comprehensi

None of those adjectives—important, significant, serious, major or big—can be considered either positive or negative. They can all indicate good or bad things:
Invasive species are an especially important problem when it comes to waterways.
An important problem of the industrial revolution was the preservation of flour.
Human influenza is a viral infection tha

Thank you very much for the great examples.

You can "test" the validity of a collocation by using a corpus (a compendium of text that has been validated.) There are several good sites that the EF teachers use frequently.

One is fraze.it. This uses newspaper and magazine sources, and gives the source publication.
You can see the usage of "important problem" here.

Wow! Thank you very much for all the useful sites. I'll make the most of them.

teacherJapanWhen you use the word 'problem', you wouldn't use 'imporant' to describe it?When I look it up in a collocation dictionary, it says 'problem' is often used with 'serious, major, big.'

See this: