Determinations of the couplings of $N N (n pi) (n geq 1)$ are reported. The study is based on both a quark model of nucleon and a chiral field theory of mesons. The coupling of $N N pi$ is predicted and is in agreement with current value. It shows that the coupling $ N N 2 pi $ is resulted in the nature that pion is a Goldstone boson. The couplings of $N N (n pi) (n geq 2)$ are predicted by this approach.
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