  With the observations of the Solar Dynamics Observatory, we present the
slipping magnetic reconnections with multiple flare ribbons (FRs) during an
X1.2 eruptive flare on 2014 January 7. A center negative polarity was
surrounded by several positive ones, and there appeared three FRs. The three
FRs showed apparent slipping motions, and hook structures formed at their ends.
Due to the moving footpoints of the erupting structures, one tight
semi-circular hook disappeared after the slippage along its inner and outer
edge, and coronal dimmings formed within the hook. The east hook also faded as
a result of the magnetic reconnection between the arcades of a remote filament
and a hot loop that was impulsively heated by the under flare loops. Our
results are accordant with the slipping magnetic reconnection regime in 3D
standard model for eruptive flares. We suggest that complex structures of the
flare is likely a consequence of the more complex flux distribution in the
photosphere, and the eruption involves at least two magnetic reconnections.
