posílat / poslat — to send

"To send" is the aspect pair posílat / poslat — a verb you'll use constantly for messages, money, emails, parcels, and greetings. The imperfective posílat is for sending as a habit or an ongoing process ("I send my parents money every month"); the perfective poslat is one completed dispatch ("I'll send you the address"). The pair is a good study in how far the two halves can drift apart: they share a root but conjugate in different classes, and the perfective even changes a consonant — s → š — in its present stem.

The two halves, side by side

The imperfective posílat is a tidy Class V (-á-) verb, conjugated just like dělat, built on the long stem posíl-. The perfective poslat is Class I, with -e- endings on the short stem pošl- — note the š and the dropped vowel. As always with a perfective, its present-shaped forms carry future meaning.

The posí- / pošl- alternation

This is the shape to memorize. The two halves split into two stems:

• Imperfective posíl- — long í, kept s, full vowel: posílám, posíláš, posílá...
• Perfective pošl- — short, with s → š and no vowel before the -l-: pošlu, pošleš, pošle...

The infinitives keep s in both (posílat, poslat), but the perfective present swaps in š. So you get poslat (infinitive) → pošlu (present-future). Writing poslu or pošlám is the typical slip — keep the long imperfective and the soft-š perfective firmly apart.

The first sentence is one finished act in the future (pošlu); the second is a recurring habit (posílám).

What the verb governs: accusative + dative

Both halves take the thing sent in the accusative and the recipient in the dative — the same double-object frame as English "send someone something," but Czech uses cases, not word order. The pattern is send [dative recipient] [accusative thing].

In Pošlu ti dopis, dopis ("letter") is accusative and ti ("to you") is the dative recipient — the same kind of indirect object dative you meet with dávat / dát ("to give"). The recipient clitics are mi, ti, mu, jí, nám, vám, jim.

poslat pro — to send for someone

With pro plus the accusative, poslat means "to send for" — to dispatch someone or something to fetch a person. You're not sending an object to someone; you're sending word for someone to come.

So poslat někomu něco = "send someone something," but poslat pro někoho = "send for someone." The preposition flips the whole meaning from delivering to to summoning.

The imperative

The imperative splits by aspect. The perfective pošli / pošlete keeps the š of the present stem and is the normal command for one act of sending; the imperfective posílej / posílejte asks for a repeated or ongoing habit.

For a single "send it!" use the perfective pošli; the imperfective posílej means "keep sending."

The past tense

Both halves form the past from the l-participle plus the auxiliary, agreeing in gender and number. Note that the past keeps s in both (posílal, poslal) — the š lives only in the perfective present and imperative.

The imperfective posílali jsme si dopisy paints a habit ("we used to send"), while the perfective poslal jsem ti soubor reports one completed send.

The future tense

The two halves build the future differently, which is exactly where aspect earns its keep:

• Imperfective future = budu
  • the infinitive posílat: budu posílat, budeš posílat... — sending as an ongoing or repeated future activity.
• Perfective future = just pošlu. There is no budu; you never say budu poslat.

Common mistakes

For an action happening at this moment, use the imperfective posílám; pošlu means "I will send."

The perfective is already future. Putting budu in front of it is ungrammatical.

The perfective present stem is pošl-, with š: pošlu, pošleš, pošle. The plain s belongs to the infinitive poslat and the past poslal.

The recipient stands in the dative (ti, "to you"), not the accusative (tě). Poslal jsem tě would mean "I sent you" as an object — as if mailing the person.

Key takeaways

• posílat = imperfective (habit, in progress); poslat = perfective (one completed send).
• Two stems: imperfective posíl- (long, with s) vs perfective present pošl- (with s → š).
• Government: poslat někomu (dative) něco (accusative) = send someone something.
• poslat pro
  • accusative = "send for someone"; poslat někomu = "send to someone."
• Perfective future = just pošlu; imperfective future = budu posílat. Never budu poslat.