  Microlensing can provide a useful tool to probe binary distributions down to
low-mass limits of binary companions. In this paper, we analyze the light
curves of 8 binary lensing events detected through the channel of
high-magnification events during the seasons from 2007 to 2010. The
perturbations, which are confined near the peak of the light curves, can be
easily distinguished from the central perturbations caused by planets. However,
the degeneracy between close and wide binary solutions cannot be resolved with
a $3\sigma$ confidence level for 3 events, implying that the degeneracy would
be an important obstacle in studying binary distributions. The dependence of
the degeneracy on the lensing parameters is consistent with a theoretic
prediction that the degeneracy becomes severe as the binary separation and the
mass ratio deviate from the values of resonant caustics. The measured mass
ratio of the event OGLE-2008-BLG-510/MOA-2008-BLG-369 is $q\sim 0.1$, making
the companion of the lens a strong brown-dwarf candidate.
