Fertilizer (n) ? natural and man-made
material that is spread on soil to help plants to grow.
Flood (n) ? an overflowing of water onto land that is normally
Food chain (n) ? a series of organisms in which the organisms
in each level of the series use organisms in the next lower level as
Forest (n) ? an area of land that is covered with a dense
growth of trees, shrubs and plants.
Fossil fuel (n) ? a non-renewable source of energy that comes
from the buried remains of plants and animals that lived millions of
years ago (such as oil, coal and natural gas).
Fresh water (n) ? water that has a low amount of salt and
Freeze (v) ? to change a liquid into solid by cooling the