In this paper, we first establish the local well-posednesss for the Cauchy problem of a generalized Camassa–Holm (gCH) equation in Besov spaces Bp,11+1p\documentclass[12pt]{minimal}
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\begin{document}$$B^{1+\frac{1}{p}}_{p,1}$$\end{document} with 1≤p<+∞.\documentclass[12pt]{minimal}
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\begin{document}$$1\le p<+\infty .$$\end{document} Then we gain two blow-up criterions, and present two new blow-up results. Finally, we prove the ill-posedness of the gCH equation in critical Besov spaces B2,r32,r∈(1,+∞].\documentclass[12pt]{minimal}
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\begin{document}$$B^{\frac{3}{2}}_{2,r},~r\in (1,+\infty ].$$\end{document}