Best key ever: Remember the acronym "HOMES"- and then link up Huron, Ontario, Michigan, Erie, and Superior. And that's all the Great Lakes.
it turns into oxygen
If all the Great Lakes dried up, the climate would be such that North America would be an extremely arid desert from central Canada to the southern tip of Texas and from Boston to LA. Keep in mind that the Great Lakes is fully 25% of the fresh water supply of the Earth. It feeds and is fed by roughly 75% of the river systems in North America. In short, by the time the Great Lakes dried up, most if not all the animal life, including humans, would be dead.
Salt
Canada shares the Great Lakes with the United States. The Great Lakes are make up of Lakes Huron, Ontario, Michigan, Superior, and Erie.
The sun's heat.
Salt
The water never dries up because four of the Great Lakes are feeding into the Niagara River.
Eh...they are lakes that have dried up. Which is of course why they are called "dry" lakes. Salton Sea in south-east California is a sea (a salty lake) that is rapidly drying up due to the ongoing droughts that have plagued California on and off for several decades now. Aral Sea south of the Russian Federation is another such lake that is disappearing for the lack of rainfall and streams to keep it filled. With the global climate change more and more lakes/seas are drying up due to the resulting extended and more severe droughts. Which is to say the Earth is getting more dry lakes than ever before in modern history.
the five great lakes are called great because they are so big and they take up more of the united states
YES
If you are talking about any oasis (pl?) then they do indeed dry up at times.