Salt water (n) ? water that has a high
level of salt, such as in oceans and seas.
Sand (n) ? very small, loose grains of disintegrated rock.
Science (n) ? an area of knowledge that is studied.
Sea (n) ? the ocean.
Sediment (n) ? material produced by erosion that settles on the
bottom of lakes and oceans.
Sewage (n) ? human waste.
Sinkhole (n) ? a hole caused when an area of land collapses,
which is usually caused because an underground layer of limestone
rock has worn away.
Sleet (n) ? precipitation that consists of frozen or partially
Smog (n) ? air pollution.
Snow (n) ? precipitation in the form of ice crystals.
Soil (n) ? the upper layer of the Earth that can be dug up and
in which plants grow.
Solar energy (n) ? a renewable source of energy that comes from
the heat of the sun.
Solid (n) ? a substance that is hard and keeps its own shape.
Species (n) ? a category of organisms (for example, the species
of dogs includes different breeds or types of dogs, such as poodles,
German Shepherds and Golden Retrievers).
Spring (n) - Naturally occurring source of
water flowing from the ground.
Stream (n) ? a medium-sized body of flowing fresh water.
Sulfur Dioxide (n) - A Criteria Pollutant Sulfur Dioxide (SO2) is produced by power plants and industries that burn fossil fuels that contain sulfur, such as coal and oil, and by the phosphate industry through its production of sulfuric acid.
Surface water (n) ? water that remains on top of the Earth
(such as in streams, lakes, rivers, ponds, wetlands and reservoirs).
Sun (n) ? The central star of the solar
Swamp (n) ? a wetland that is mostly covered by shrubs and