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"Hizo" is a form of "hacer", a transitive verb which is often translated as "to do". "Hacía calor" is a phrase which is often translated as "it was hot". Learn more about the difference between "hacía calor" and "hizo" below.
hacía calor( 
ah
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see
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ah
kah
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lohr
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (general)
a. it was hot 
Cuando llegamos a la isla, hacía calor así que fuimos a darnos un baño al mar.When we arrived on the island, it was hot, so we went for a swim in the sea.
hacer(
ah
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sehr
)A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
2. (to produce)
b. to prepare 
Nos reuniremos este fin de semana para hacer la presentación.We will meet this weekend to prepare the presentation.
3. (to create)
a. to make 
Hoy les enseñaré a hacer su propio sitio web.Today I'll show you how to make your own website.
a. to make 
Estoy ocupado haciendo los preparativos para la fiesta.I'm busy making preparations for the party.
a. to do 
Me mandó que lavara los platos pero ya lo había hecho.He told me to wash the dishes but I had already done it.
6. (to acquire)
7. (to cause)
8. (to imagine)
12. (to behave)
13. (to gross)
14. (to take time)
An impersonal verb is a verb with no apparent subject (e.g., Llueve en España.).
16. (time)
hacerse
A reflexive verb is a verb that indicates that the subject performs an action on itself (e.g., Miguel se lava.). 
a. to make oneself 
Creo que voy a hacerme un puré de zanahorias esta noche.I think I'm going to make myself some carrot soup tonight.
A pronominal verb always uses a reflexive pronoun. (e.g., Te ves cansado.).
20. (to feign)
a. to pretend 
No te hagas el santo; tú también te equivocas.Don't pretend to be a saint; you make mistakes, too.
21. (to turn into)
a.  no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Ya va siendo hora de que se haga cortar el pelo.It's about time he had his hair cut.
Vamos a hacernos pintar la casa después del verano.We're going to have the house painted after the summer.
23. (to manage to)
a.  no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Daniela solo ayuda en clase para hacerse ver.Daniela only helps out in class to get noticed.
Deberíamos darle una oportunidad para hacerse oír.We should give him a chance to be heard.
25. (to appear)
a. to feel 
Hoy se me hizo muy largo esperando los resultados de la prueba.Today felt really long waiting for my test results.
b.  no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
El curso se me está haciendo aburrido.I'm finding the course boring.
La película se me hizo interminable.The movie seemed interminable.