When ‘it’ is the subject of a sentence, the subject is understood from the context. ‘lo’ is an object pronoun, never used as a subject. There is no subject pronoun meaning ‘it’.

“It is the best restaurant...”“Es el mejor restaurante...”

Ser  classifies and identifies; it tells what something is like by nature

(By extension, describes origin, profession, social class and age group, etc.)

“El violín es un instrumento delicado; es difícil de tocar bien.”

‘Ser’ can also can be a synomym for “to occur”: El concierto es aquí.

Estar  describes the state, condition or location something happens to be in. It also forms progressive tenses to narrate activities in progress.

“Mi violín está aquí. Estoy tocándolo aunque está en malas condiciones.”

With respect to location/places...

‘a’ means ‘to’ - -   Van... a Bob Evans.

‘en’ means ‘in’/‘at’ - -    Cenan en Bob Evans.  Trabajo en Bob Evans.

tener = to have; to possess

Tener que = to have to; to be obligated to

5.  ‘before’ and ‘after’ can be prepositions.

If a verb follows a preposition, it will normally be an infinitive

sin dormir ? without sleeping

después de comer - after eating

insisti en hablar- I insist on talking

para comprender- in order to understand

¡Ojo! When followed by ‘que, these are now conjunctions.

(I fell asleep after she left. Me dormí después [de] que ella salió.)

Use the definite article to speak of ...

a. a specific item or group of specific items

¿Quién trajo el vino que está en la mesa? (Just like in English)

b. a category of something or a generalized concept.

Me gusta el vino (en general).(Unlike in English)

La filosofía es abstracta.(Unlike in English)

Omit the article to refer to...

a. part or some (of) something (like English)

Hay (“some”) huevos en el refrigerador.(Just like in English)

‘Nos’ = ‘us’, ‘to us’, ‘ourselves’(Nosotros = ‘we’; nuestro= ‘our’)

‘Para’ ‘Points’ to the recipient of a gift, a date in the future, or a goal

‘Por’ Describes our path through time or space (along the beach, on a plane, through the woods), the duration of an activity (por una semana)

Looks back to the motive for an action(¿Por qué?)

Describes rates, exchanges, substitutions or the object of an errand

often are not translated to Spanish. They are more often devices that help us to form questions in English.(‘hacer’= to make/do)

“Do you work here?”“¿Trabajas aquí?”

“Did you sleep well?” “Dormiste bien?”

Write in a straight-forward fashion. Start with and build upon the structures you already know in Spanish rather than beginning with subtle and sophisticated English phrases and trying to magically transform them into Spanish.