earth
                    - Do you know Earth Day?-Sure, it _______ in 1970 to tell us to protect our earth.
 - Australia is in the south of the earth so the seasons there are the opposite of .
 - Did you know the Earth is home to __________ animals?
 - Australia is in the south of the earth so the seasons there are the opposite of .
 - Did you know the Earth is home to __________ animals?
 - ___________ from space, the earth looks like a blue ball.
 - The teacher said the earth ________around the sun.
 - Have you heard of Earth Day ?—-Yes . The first Earth Day ______ in 1970 to educate us to protect our planet .
 - What on earth are the police busy with?—They have been looking into how the plane crash _______.