When you imagine the South Pole，what do you see？A pole with flags sticking out in an empty，frozen，white openness？Actually，there’s more than one South Pole—and none of them exactly fits the above     1     (describe).

If you think of the earth as a     2     (spin) basketball balanced on the tip of a finger，the place where the fingertip touches the ball is what     3     (call) the geographic South Pole.This South Pole is an imaginary point.There’s no pole with flags there，just a stick and a sign honoring the first explorers     4     (reach) the spot in 1911.

A short distance from the geographic South Pole is a ceremonial South Pole—    5     actual pole with flags from some countries.Far，far away is the magnetic South Pole—the South Pole     6     which a compass would point you.Its current location is 1,800 miles away from the geographic South Pole，in the Southern Ocean，so far north     7     it’s not even in the Antarctic circle.The ocean­going magnetic South Pole is     8     (natural) unmarked，but if you happen to be there，you     9     (notice)：Your compass needle moves aimlessly.

There is still another South Pole：the pole of inaccessibility，defined as the place in Antarctica that is the     10     (far) from any shore.