  We perform the simultaneous $|V_{ub}|$ and $|V_{cb}|$ extractions with only
the exclusive $\Lambda_b$ decays of $\Lambda_b\to (p,\Lambda_c^+)\mu\bar
\nu_\mu$, $\Lambda_b\to p\pi^-$ and $\Lambda_b\to \Lambda_c^+ (\pi^-, D^-)$. We
obtain that $|V_{ub}|=(3.7\pm 0.3)\times 10^{-3}$ and $|V_{cb}|=(45.9\pm
2.7)\times 10^{-3}$. Our value of $|V_{ub}|$ is larger than that of $(3.27\pm
0.15\pm 0.16\pm 0.06)\times 10^{-3}$, previously extracted by the LHC
Collaboration from the exclusive $\Lambda_b$ decays also, but nearly identical
to $(3.72\pm 0.19)\times 10^{-3}$ from the exclusive $B$ decays. On the other
hand, our extracted result of $|V_{cb}|$ favors the value of $(42.2\pm
0.8)\times 10^{-3}$ from the inclusive $B$ decays.
