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"Caer mal" is an intransitive verb phrase which is often translated as "to rub ... the wrong way", and "caer bien" is a transitive verb phrase which is often translated as "to like". Learn more about the difference between "caer mal" and "caer bien" below.
caer mal( 
kah
-
ehr
mahl
)An intransitive verb phrase is a phrase that combines a verb with a preposition or other particle and does not require a direct object (e.g., Everybody please stand up.).
1. (to dislike)
a. to rub ... the wrong way  (United States)
Regionalism used in the United States
Su novio nuevo me cae mal, pero no sé por qué.Her new boyfriend rubs me the wrong way, but I don't know why.
b. to rub ... up the wrong way  (United Kingdom)
Regionalism used in the United Kingdom
Ya no soporto trabajar en esa oficina porque todos me caen mal.I can't stand working in that office any longer because everyone rubs me up the wrong way.
2. (culinary)
a. to not sit well 
El queso me cayó mal, y ahora tengo ganas de vomitar.The cheese didn't sit well with me and now I feel like I'm going to throw up.
caer bien( 
kah
-
ehr
byehn
)A transitive verb phrase is a phrase that combines a verb with a preposition or other particle and requires a direct object (e.g., take out the trash.).
a. to like 
¿Te cae bien la nueva profesora de inglés?Do you like the new English teacher?
Sus hermanos me caen muy bien.I like her brothers a lot.
caerse bien
A pronominal verb phrase combines a verb with a preposition or other particle and always uses a reflexive pronoun. (e.g., Se dio cuenta del problema.)
a. to like each other 
Ya sabes que tu hermano y yo no nos caemos bien.You know your brother and I don't like each other.
b. to get on 
Es evidente que Jorge y Tere no se caen bien.It's obvious that Jorge and Tere don't get on.