The best replacement for idioms is proverbs.

The best alternatives to idioms are rated as following:
★★★★★  proverbs
★★★★  sayings
★★★★  idiomatic expressions
★★★★  slang
★★★★  phrases
★★★  metaphors
★★  cliches
★★  phrasal verbs
★★  figures of speech
★★  expressions
★  figure of speech
★  idiomatic expression
★  analogies
★  simile
  hyperboles
  colloquialisms
  verbal phrases
  euphemisms
  patterns
  figurative language

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Speaking about idioms, one probably shouldn't forget about tener.

Other search terms related to idioms and their ratings are:
★★★★★ tener
★★★★★ examples
★ meaning and sentence
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