Would it not be a coral reaf? Home to hundreds of fish and under water plants?
This sentence would probably be a citation in APA style. Citations on research papers are very important since they give due credit to the original owner of the statement. Statements that don't have citations tells the readers that those statements are of the researcher/s alone which would be a problem for them if found out that it wasn't theirs to begin with. This would result to a work of plagiarism which is a grave sin in constructing research papers and is more equated with the act of stealing.
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Getting educated outdoors or experimental education. Learning from experience, trying out different things, seeing how they work. Testing different theories, trying different things, not based on a specific curriculum. Outdoor learning is basically free learning, no specific schedule, just trying things out, seeing what happens, like seeing how a tree grows, growing plants, just different experiments, free learning.
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