In this present work, we study the scattering of a pseudoscalar
meson off one ground state octet baryon in covariant baryon
chiral perturbation theory up to the next-to-next-to-leading order. We
remove the power counting breaking terms with the extended-on-mass-shell
scheme. We perform the fi?rst combined study of the pion-nucleon
and kaon-nucleon scattering data and show that the covariant baryon
Chiral perturbation theory can provide a reasonable description of the
experimental data for both channels.