(as) dull as dishwater
US /əz dʌl əz ˈdɪʃˌwɔtər/
UK /əz dʌl əz ˈdɪʃˌwɔtər/

1.
索然无味, 枯燥乏味
very boring or uninteresting
:
•
The movie was as dull as dishwater, I almost fell asleep.
这部电影索然无味,我差点睡着了。
•
His presentation was as dull as dishwater, full of facts but no passion.
他的演讲索然无味,只有事实,没有激情。
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