Comment on "Modified F(R) Ho\v{r}ava-Lifshitz gravity: a way to   accelerating FRW cosmology" by M. Chaichian, S. Nojiri, S. D. Odintsov, M.   Oksanen, A. Tureanu
  The partial Hamiltonian analysis of the Ho\v{r}ava-type action presented in the paper by M. Chaichian, S. Nojiri, S. D. Odintsov, M. Oksanen, A. Tureanu (Class. Quant. Grav. 27 (2011) 185021) is incorrect; for the authors' choice of variables, a covariant shift, instead of a contravariant shift which is the one usually used in General Relativity (GR) in ADM variables, the true algebra of constraints differs from what they presented. The algebra of constraints for their choice of variables is explicitly given for GR and compared with the standard algebra. 
N. Kiriushcheva, P. G. Komorowski, and S. V. Kuzmin
gr-qc hep-th