Question

how do you conjugate ser and estar, and how do you know when to use ser and when to use estar?

Answer 1

Well, we know that both "ser" and "estar" mean "to be."

We use SER when we're talking about a lasting, permanent characteristic.
Like physical features,
or traits, and physical descriptions.
Also, when we're talking about the time.

We use ESTAR when we're talking about temporary conditions,
such as emotions, and state of being,
or the weather (for the most part),
or location,
or actions. (I am learning -----> Yo ESTOY aprendiendo)

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If there are any specific examples where you're unsure of whether to use SER or ESTOY, let me know. I'll explain it for you.

Answer 2

Oh, and I'll show you how to conjugate both SER and ESTAR, in the present tense, real quick:

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Soy - I am

Eres - You are

Es - (He/She/It) is

Somos - We are

Son - They are

~~~~~~~~~~~~~~

Estoy - I am

Estás - You are

Está - (He/She/It) is

Estamos - We are

Están - They are

Answer 3

+

Sois - You are (plural)

Estáis - You are (plural)

Answer 4

Note: the vosotros forms (sois and estáis) are mostly only used in Spain. Also, it is a familiar form on par with tû. You are (plural, formal) would be "ustedes son"