  We investigate the $B^+\to J/\psi \phi K^+$ decay via various rescattering
diagrams. Without introducing genuine exotic resonances, it is shown that the
$Z_{cs}(4000)$, $Z_{cs}(4220)$ and $X(4700)$ reported by the LHCb collaboration
can be simulated by the $J/\psi K^{*+}$, $\psi^\prime K^+$ and $\psi^\prime
\phi$ threshold cusps, respectively. These cusps are enhanced by some nearby
triangle singularities. The $X(4685)$ with $J^P=1^+$ cannot be well simulated
by the threshold effects in our model, which implies that it may be a genuine
resonance.
