ignorar  to not know

imaginar  to imagine

impedir  to prevent/block

importar  to matter

imprimir  to print

incluir  to include

indicar  to indicate/signal

iniciar  to start/initiate

influir  to influence

inscribir  to register/enroll

inscribirse  to sign up/register

insistir  to insist

intentar  to try/attempt

interesar  to (be of) interest

interesarse  (to take an interest in)

interrumpir  (to interrupt)

introducir  (to insert/enter)

invertir  (to invest)

invitar  (to invite)

ir  (to go)

irse  (to go away)