think hard

[optimistic pessimist]

Hi teachers

Do you say think hard?

e.g. I thought really hard to solve the question, but I couldn't.

If hard doesn't fit, what adverbs go with think?

Hard is a basic word, but I think it's hard to use it correctly.

Thank you

OP

[paulmoss]

Dear pessimist,
This is in fact a common English collocation, which is sometimes used as part of a longer phrase" Think long and hard". "Think deeply" is another possible combination.
Yours