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"Modificar" is a transitive verb which is often translated as "to modify", and "revisar" is a transitive verb which is often translated as "to review". Learn more about the difference between "modificar" and "revisar" below.
modificar(
moh
-
dee
-
fee
-
kahr
)A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
modificarse
A pronominal verb always uses a reflexive pronoun. (e.g., Te ves cansado.).
a. to change 
La ciudad se modificó de la noche a la mañana con la llegada de los inmigrantes.The city changed overnight with the arrival of immigrants.
revisar(
rreh
-
bee
-
sahr
)A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
1. (to examine)
a. to review 
Nuestro abogado revisará el contrato antes de proceder.Our lawyer will review the contract before proceeding.
b. to check 
Revisa tu respuesta para asegurarte que sea correcta.Check your answer to be sure it is correct.
c. to inspect 
Debes revisar tu auto nuevo antes de manejarlo a casa por primera vez.You should inspect your new car before driving it home for the first time.
d. to go over 
El auditor revisó las cuentas en busca de anomalías.The auditor went over the books to look for anomalies.