__ is rain that contains harmful amounts of poisons due to pollution.

An __ is a narrow strip of land that connects two larger land areas. 

A __ is a large expanse of land that can be flat or have a gentle roll. 

__ means to circle around something. 

The __ is the process in which water is used and reused on Earth, including precipitation, collection, evaporation, and condensation. 

The __ is a long, narrow band of volcanoes surrounding the Pacific Ocean. 

__ is the change of liquid water to water vapor. 

__ is the average weather in an area over a long period of time. 

A __ is an area that receives reduced rainfall because it is on the side of a mountain facing away from the ocean. 

The water contained inside Earth's crust is called __. 

___ is the result of water vapor changing to  liquid or solid state. 

An __ is one of two days each year when the sun is directly overhead of the Equator. 

A __ is a place where two tectonic plates grind against each other. 

__ is the process by which weathered bits of rock are moved elsewhere by water, wind, or ice. 

A __ is a large, unbroken mass of land. 

An __ is an event in which the ground shakes or trembles, brought about by the collision of tectonic plates. 

A __ is a large body of ice that moves slowly across land. 

__ is the water that falls on the ground as rain, snow, sleet, hail, or mist. 

__ is a process that makes salt water safe to drink. 

A __ is the part of a continent that extends into the ocean in a plateau, then drops sharply to the ocean floor.  

__ are on of the 16 pieces of Earth's crust. 

An __ is an imaginary line that runs through Earth's center from the North Pole to the South Pole. 

A __ is a giant ocean wave caused by volcanic eruptions or movement of the Earth under the ocean floor. 

A __ is a flat area that rises above the surrounding land. 

A __ is an area where sand, silt, clay, or gravel is dropped at the mouth of a river. 

__ is the process by which Earth's surface is worn away by natural forces. 

The __ is the layer of gasses surrounding Earth. 

A __ is one of two days of the year when the sun reaches its northernmost of southernmost point. 

A ___ is a complete trip of Earth around the sun. 

A __ is a long, narrow, steep-sided cut on the ocean floor.