δΊ’ hu4 δΊ’
ι€š tong1 ι€š
ζœ‰ you3 ζœ‰
ζ—  wu2 η„‘
  1. (idiom) mutual exchange of assistance; to benefit from each other's strengths and make up each other's shortfalls; to reciprocate with material assistance; to scratch each other's back

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