SER vs. ESTAR…
Although defining these two verbs can become subtle and subjective as your Spanish becomes more and more sophisticated, HERE you have a basic and purposedly concise definition of the core meaning of these verbs.
SER= DEFINITION
ESTAR= LOCATION (temporary situation)
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Did you KNOW that when you DEFINE, S E R is the verb to use?
For instance: ES la luna: A name could define you at one point, so… S E R is your friendly verb for DEFINITION ;)
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E S T A R shows LOCATION (or temporary condition);
For instance: La luna está sobre los árboles (both: location AND temporary condition -Moon is there NOW… It could be elsewhere later ;)