Learn Hardcore Spanish (Latin America): La secretaria imprimió la nota y nos la envió por correo electrónico. - The secretary printed the note and sent it to us by e-mail.

Imprimió is the third-person singular preterite form of imprimir. In Spanish, regular –IR and –ER verbs in the preterite add –ió to the stem (imprim- + ió). Because the ending –ió is a stressed syllable and follows the rule that words ending in a vowel need an accent on the stressed vowel, we write imprimió with an accent on the o.

Why are both imprimió and envió in the preterite tense instead of the imperfect?

The preterite tense describes completed actions at specific points in the past. Here, printing the note and sending it by email are finished events. The imperfect would be used for habitual actions or background descriptions (e.g., “La secretaria imprimía notas todos los días”), but since this sentence reports two single, completed actions, the preterite is correct.

What do nos and la mean in nos la envió?

Nos is the indirect object pronoun meaning “to us.”
La is the direct object pronoun meaning “it,” referring back to la nota.
So nos la envió literally means “she sent it to us.”

Why is the order nos la rather than la nos?

Spanish clitic pronouns follow a fixed order when two appear together: the indirect object pronoun (nos) always comes before the direct object pronoun (la). Swapping them (la nos) is ungrammatical.

Why are the pronouns placed before envió instead of attached after it?

With finite conjugated verbs (like envió in the preterite), clitic pronouns go before the verb (this is called proclisis). You only attach pronouns after the verb (enclisis) when you have an infinitive, a gerund, or an affirmative command. For example:

Infinitive: Quiero enviárnosla.
Gerund: Está enviándonosla.
Affirmative command: Envíanosla.

Why is por used in por correo electrónico? Could you use en?

Por indicates the means or medium by which something is done—in this case, by way of email. While English uses “by email,” Spanish standardly uses por correo electrónico. Saying en correo electrónico sounds unusual; you can say en un correo electrónico only when you mean “within an email” (e.g., en un correo electrónico mencionó esto).

Is nota always feminine? Could we ever say el nota?

Nota is a feminine noun in Spanish, so it always takes la in the singular (and las in the plural). That’s why the direct object pronoun matching nota is also the feminine la. You cannot say el nota.

Can you replace envió with mandó, or correo electrónico with mail?

Yes. In Latin America mandar is a common synonym for enviar, so la secretaria mandó la nota is perfectly natural.
As for correo electrónico, many speakers—especially in informal contexts—use mail (a Spanglish borrowing) or just correo when the context is clear. In formal writing you’d stick with por correo electrónico.