"He asked" is an active voice construction in English. The subject is 'he.' The active voice equivalent is "Él preguntó" in Spanish.
"He was asked" is a passive voice construction in English. One of the equivalents in Spanish is "
se le preguntó (a él)," an example of the
pasiva refleja construction.
(The voz pasiva (passive voice) equivalent would be "Él fue preguntado.")
"
Se le olvidó" is an example of the "no-fault
se" construction in Spanish. Its literal translation is '(it) forgot itself on him.' No comparison can be made between a no-fault construction and the
pasiva refleja.
The pronoun se is used in several Spanish constructions, all yielding a different English translation.