These are affected slightly by the motion of the nucleus: a nucleus moves a little as a result of the pull of an electron orbiting it, just as the Sun wobbles slightly under the influence of the Earth's gravity.
(an electron; orbiting; it) (a nucleus; moves; a little; as a result of the pull of an electron) Context(a nucleus moves,List([58, 73))):(These; are affected slightly; by the motion of the nucleus)
a nucleus moves,List([58, 73))
an electron a nucleus These
orbiting moves are affected slightly
it
a little as a result of the pull of an electron
by the motion of the nucleus