e
Function of e
e marks the direct object of the verb.
mi toki e nimi pona = "I say good words"
Sources of confusion
Most of the confusion around e comes from not knowing what the direct object is. For example,
mi toki e sina ≠ "I talk to you"
mi toki e sina = "I say you"
Remembering what is what isn't as hard as it seems; in English, the direct object never has a preposition. So if in the sentence you're translating, the "object" has a preposition before it (such as to, for, from, etc), it's not the direct object.
"He walks towards me" = ona li tawa mi