Definite Article with Deserts, Oceans, Rivers, and Seas

Rule 7.3: Use the definite article with the names of deserts, oceans, rivers, and seas.

The Dead Sea is famous for being quite salty.
The St. Lawrence River empties the Great Lakes.
The Pacific Ocean is the deepest ocean in the world.
There is very little water in the Sahara.

Exercise 6: Fill in the blanks with a, an, or the.