The Top 5 Confusing Idioms in English

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I have found these phrases confusing.

1. All but.  "The war was all but lost."  Does that mean it was lost?  Was not lost?  Was everything except lost?  This is really bad information.  I will all but look this up in the dictionary.

2. "X of Y" as a time, such as "The time is now five of ten."  Is it 9:55?  10:05?  9:05 -- five minutes of the tenth hour??? [Update: X of Y is X minutes before Y, just as X precedes Y in the phrase].

3. Cop out.  "That's a cop out."  Is that a confession?  An excuse?  A policing? 

4. Coming soon...