think before doing

think before (doing something)

To ruminate, reflect, or consider very carefully before undertaking some action. He's the type of person who wouldn't think before jumping on a plane to some foreign country on the promise of adventure. You really ought to think before taking on such a huge responsibility.
See also: before, think
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

think before doing something

to consider the consequences before doing something. You really ought to think before you take on a job like that. I finally learned to think carefully before accepting jobs like the one I just took on.
See also: before, think
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in periodicals archive ?
I'm not asking the public not to bet, or to boycott the National, but I am asking them to think before doing so.