| Idiom | Meaning | Example | 
| silver spoon | 
(See born with a silver spoon in his mouth)
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| silver-tongued | 
nice-talking, smooth talker  
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A silver-tongued salesman sold me this car, but I can't drive!
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| simmer down | 
control your anger, chill out, cool off
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Simmer down, Sassy. You are very angry. Try to control yourself.
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| sin bin (hockey) | 
(See the sin bin)
 | 
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| sing his praises | 
praise him a lot, talk  in glowing terms
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His mom is always singing his praises, saying he's a good boy.
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| sing up a storm | 
sing loud, sing vigorously
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After dinner we gathered around the piano and sang up a storm.
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| single file | 
a single row of people, one by one
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We marched single file through the prison door.
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| single out | 
choose one person from a group
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Why does the priest single me out for extra duties? Why me?
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| sinking feeling | 
feeling of failure; despair
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When I saw the ambulance at our house, I got a sinking feeling.
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| sit in judgement on | 
judge someone's actions, evaluate
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Gary is afraid because you sit in judgement on whatever he does.
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