Modified gravity: walk through accelerating cosmology
  We review the accelerating (mainly, dark energy) cosmologies in modified
gravity. Special attention is paid to cosmologies leading to finite-time future
singularities in $F(R)$, $F(G)$ and $\mathcal{F}(R,G)$ modified gravities. The
removal of the finite-time future singularities via addition of $R^2$-term
which simultaneously unifies the early-time inflation with late-time
acceleration is also briefly mentioned. Accelerating cosmology including the
scenario unifying inflation with dark energy is considered in $F(R)$ gravity
with Lagrange multipliers. In addition, we examine domain wall solutions in
$F(R)$ gravity. Furthermore, covariant higher derivative gravity with scalar
projectors is explored.
