I wonder why．There's a hole in the sky :：and other questions about the environment / I wonder why there's a hole in the sky :: and other questions about the environment / I wonder why there's a hole in the sky :and other questions about the environment Other title：There is a hole in the sky and other questions about the environment There is a hole in the sky and other questions about the environment There's a hole in the sky and other questions about the environment I wonder why the sea is salty :: and other questions about the oceans / I wonder why the sea is salty :and other questions about the oceans I wonder why the sun rises :: and other questions about time and seasons / I wonder why snakes shed their skin :: and other questions about reptiles /