puts a dumper on
To put a damper on
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http://dictionary.cambridge.org/ru/%D1%81%D0%BB%D0%BE%D0%B2%D0%B0%D1%80%D1%8C/%D0%B0%D0%BD%D0%B3%D0%BB%D0%BE-%D1%80%D1%83%D1%81%D1%81%D0%BA%D0%B8%D0%B9/put-a-damper-on-sth