Use shadow when talking about the darkness around a specific object. Ex: If you stand outside on a sunny day, you will see your shadow. Use shade when you are talking about an area that is sheltered from the sun. Ex: It is so hot outside, it feels good to stand in the shade where the air is cooler. (This could be under a tree, in a tent, or anywhere that the sun is not shining.)

"shade" has no shape

A shadow is a recognizable shape, a sort of image. It is a countable noun. "I can hold my hands in front of a movie screen and make a shadow that looks like a bird with flapping wings." "Late in the day, I cast a shadow ten feet long." Shade is a large area of subdued light. "Let's sit in the shade of this tree, where it is cool." "In the desert, it is impossible to find any shade."

Thanks you very much.

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