短文填空At the top and the bottom of the earth there is a ______

短文填空
At the top and the bottom of the earth there is a ___________ of ice.It is very _____ there.Sometimes there is no sun for some weeks,and sometimes even some __________.The ground is covered with __________ and snow all the time.
We call _________ pieces of ice “Icebergs”.Some icebergs are bigger _________ a tall _________.Icebergs are dangerous to _________ in the sea.“Titanic”hit an iceberg and sank.Thousands of people died.