Final answer:
In geography, a bridge is a structure that connects land masses or spans across water, while an island is a piece of land surrounded by water on all sides.
Step-by-step explanation:
In geography, a bridge refers to a structure that connects two land masses or spans across a body of water. An ending ridge is a topographical feature that marks the termination of a ridge system. Bifurcation or fork refers to the division of a river into two branches. Double bifurcation refers to the division of a river into three branches, whereas trifurcation refers to the division into four branches. A dot can represent a small, temporary island or feature in a network of river channels. An island, in geography, is a piece of land surrounded by water on all sides.