Native Spanish tutor, bilingual in French, 25 years working as a conference interpreter, offering Spanish and French lessons

I love teaching since I was a teenager in Secondary School. Later on I got a diploma to teach Spanish as a second or foreign language as well as a Masters 1 in FLE (French as a foreign language) I can teach both Spanish-mother tongue- and French - bilingual- From scratch I use the target language (the one you want to learn). One of the first lessons is the use of the verbs SER or ESTAR (to BE) Why you should say SON las 4 and not ESTAN las 4 ?(It's 4 o'clock): answer = because the hours are expressed with the verb SER