A more subtle but more easily observable example is that the tides are caused by the moon's gravity, and tidal effects can occur 
(tidal effects; can occur; ) (A more subtle but more easily observable example; is; that the tides are caused by the moon's gravity, and tidal effects can occur) Context(A more subtle but more easily observable example is,List([0, 51))):(the tides; are caused; by the moon's gravity)
A more subtle but more easily observable example is,List([0, 51))
tidal effects A more subtle but more easily observable example the tides
can occur is are caused
that the tides are caused by the moon's gravity, and tidal effects can occur
by the moon's gravity